CENOVUS ENERGY INC. (SEC Filing Page | XBRL Cloud Viewer | XBRL Instance)

Line Label Object Class Period Type Balance Report ElementName
1 100000 - Document - Document and Entity Information Network

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2 Implied Table Table

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3 Document And Entity Information [Abstract] Abstract cve:DocumentAndEntityInformationAbstract
4 Document Type Concept (Submission Type) For Period dei:DocumentType
5 Amendment Flag Concept (Yes/No) For Period dei:AmendmentFlag
6 Document Period End Date Concept (Date) For Period dei:DocumentPeriodEndDate
7 Document Fiscal Year Focus Concept (Year) For Period dei:DocumentFiscalYearFocus
8 Document Fiscal Period Focus Concept (Fiscal Period) For Period dei:DocumentFiscalPeriodFocus
9 Trading Symbol Concept (Text/String) For Period dei:TradingSymbol
10 Entity Registrant Name Concept (Text/String) For Period dei:EntityRegistrantName
11 Entity Central Index Key Concept (CIK Number) For Period dei:EntityCentralIndexKey
12 Current Fiscal Year End Date Concept (Month/Day) For Period dei:CurrentFiscalYearEndDate
13 Entity Current Reporting Status Concept (Yes/No) For Period dei:EntityCurrentReportingStatus
14 Entity Common Stock, Shares Outstanding Concept (Shares) As Of dei:EntityCommonStockSharesOutstanding
15 100010 - Statement - Consolidated Statements of Earnings (Loss) Network

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 http://www.cenovus.com/20181231/taxonomy/role/StatementConsolidatedStatementsOfEarningsLoss
16 Implied Table Table

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17 Income Statement [Abstract] Abstract ifrs-full:IncomeStatementAbstract
18 Revenues Abstract ifrs-full:RevenueAbstract
19 Gross Sales Concept (Monetary) For Period Credit cve:RevenueFromGrossSales
20 Less: Royalties Concept (Monetary) For Period Debit ifrs-full:RoyaltyExpense
21 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
22 Expenses Abstract ifrs-full:MaterialIncomeAndExpenseAbstract
23 Purchased Product Concept (Monetary) For Period Debit ifrs-full:RawMaterialsAndConsumablesUsed
24 Transportation and Blending Concept (Monetary) For Period Debit cve:TransportationAndBlendingExpense
25 Operating Concept (Monetary) For Period Debit ifrs-full:OperatingExpense
26 Production and Mineral Taxes Concept (Monetary) For Period Debit cve:ProductionAndMineralTaxes
27 (Gain) Loss on Risk Management Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnChangeInFairValueOfDerivatives
28 Depreciation, Depletion and Amortization Concept (Monetary) For Period Debit ifrs-full:DepreciationAmortisationAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
29 Exploration Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseArisingFromExplorationForAndEvaluationOfMineralResources
30 General and Administrative Concept (Monetary) For Period Debit cve:GeneralAndAdministrativeExpenses
31 Onerous Contract Provisions Concept (Monetary) For Period Debit cve:OnerousContractExpense
32 Finance Costs Concept (Monetary) For Period Debit ifrs-full:FinanceCosts
33 Interest Income Concept (Monetary) For Period Credit ifrs-full:FinanceIncome
34 Foreign Exchange (Gain) Loss, Net Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
35 Revaluation (Gain) Concept (Monetary) For Period Credit ifrs-full:GainLossRecognisedAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
36 Transaction Costs Concept (Monetary) For Period Debit ifrs-full:AcquisitionrelatedCostsRecognisedAsExpenseForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
37 Re-measurement of Contingent Payment Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseInContingentLiabilitiesRecognisedInBusinessCombination
38 Research Costs Concept (Monetary) For Period Debit ifrs-full:ResearchAndDevelopmentExpense
39 (Gain) Loss on Divestiture of Assets Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnDisposalsOfNoncurrentAssets
40 Other (Income) Loss, Net Concept (Monetary) For Period Credit ifrs-full:OtherGainsLosses
41 Earnings (Loss) From Continuing Operations Before Income Tax Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
42 Income Tax Expense (Recovery) Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
43 Net Earnings (Loss) From Continuing Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromContinuingOperations
44 Net Earnings (Loss) From Discontinued Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromDiscontinuedOperations
45 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
46 Basic and Diluted Earnings (Loss) Per Share ($) Abstract ifrs-full:BasicAndDilutedEarningsPerShareAbstract
47 Continuing Operations Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShareFromContinuingOperations
48 Discontinued Operations Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShareFromDiscontinuedOperations
49 Net Earnings (Loss) Per Share Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShare
50 100020 - Statement - Consolidated Statements of Comprehensive Income (Loss) Network

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51 Implied Table Table

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52 Statement Of Comprehensive Income [Abstract] Abstract ifrs-full:StatementOfComprehensiveIncomeAbstract
53 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
54 Other Comprehensive Income (Loss), Net of Tax Abstract ifrs-full:OtherComprehensiveIncomeAbstract
55 Items That Will Not be Reclassified to Profit or Loss: Abstract ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillNotBeReclassifiedToProfitOrLossNetOfTaxAbstract
56 Actuarial Gain (Loss) Relating to Pension and Other Post-Retirement Benefits Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnRemeasurementsOfDefinedBenefitPlans
57 Changes in the Fair Value of Equity Instruments at FVOCI (1) Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxGainsLossesOnHedgingInstrumentsThatHedgeInvestmentsInEquityInstruments
58 Items That May be Reclassified to Profit or Loss: Abstract ifrs-full:ComponentsOfOtherComprehensiveIncomeThatWillBeReclassifiedToProfitOrLossNetOfTaxAbstract
59 Foreign Currency Translation Adjustment Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeNetOfTaxExchangeDifferencesOnTranslation
60 Total Other Comprehensive Income (Loss), Net of Tax Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
61 Comprehensive Income (Loss) Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
62 100030 - Statement - Consolidated Balance Sheets Network

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63 Implied Table Table

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64 Statement Of Financial Position [Abstract] Abstract ifrs-full:StatementOfFinancialPositionAbstract
65 Assets Abstract ifrs-full:AssetsAbstract
66 Current Assets Abstract ifrs-full:CurrentAssetsAbstract
67 Cash and Cash Equivalents Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
68 Accounts Receivable and Accrued Revenues Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherCurrentReceivables
69 Income Tax Receivable Concept (Monetary) As Of Debit ifrs-full:CurrentTaxAssetsCurrent
70 Inventories Concept (Monetary) As Of Debit ifrs-full:Inventories
71 Risk Management Concept (Monetary) As Of Debit ifrs-full:CurrentDerivativeFinancialAssets
72 Assets Held for Sale Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale
73 Total Current Assets Concept (Monetary) As Of Debit ifrs-full:CurrentAssets
74 Exploration and Evaluation Assets Concept (Monetary) As Of Debit ifrs-full:IntangibleExplorationAndEvaluationAssets
75 Property, Plant and Equipment, Net Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
76 Income Tax Receivable Concept (Monetary) As Of Debit ifrs-full:CurrentTaxAssetsNoncurrent
77 Risk Management Concept (Monetary) As Of Debit ifrs-full:NoncurrentDerivativeFinancialAssets
78 Other Assets Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentAssets
79 Goodwill Concept (Monetary) As Of Debit ifrs-full:Goodwill
80 Total Assets Concept (Monetary) As Of Debit ifrs-full:Assets
81 Liabilities and Shareholders’ Equity Abstract ifrs-full:EquityAndLiabilitiesAbstract
82 Current Liabilities Abstract ifrs-full:CurrentLiabilitiesAbstract
83 Accounts Payable and Accrued Liabilities Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherCurrentPayables
84 Current Portion of Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:CurrentPortionOfLongtermBorrowings
85 Contingent Payment Concept (Monetary) As Of Credit cve:CurrentPortionOfContingentLiabilitiesRecognisedInBusinessCombination
86 Onerous Contract Provisions Concept (Monetary) As Of Credit ifrs-full:ShorttermOnerousContractsProvision
87 Income Tax Payable Concept (Monetary) As Of Credit ifrs-full:CurrentTaxLiabilitiesCurrent
88 Risk Management Concept (Monetary) As Of Credit ifrs-full:CurrentDerivativeFinancialLiabilities
89 Liabilities Related to Assets Held for Sale Concept (Monetary) As Of Credit ifrs-full:LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale
90 Total Current Liabilities Concept (Monetary) As Of Credit ifrs-full:CurrentLiabilities
91 Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:LongtermBorrowings
92 Contingent Payment Concept (Monetary) As Of Credit cve:NonCurrentPortionOfContingentLiabilitiesRecognisedInBusinessCombination
93 Onerous Contract Provisions Concept (Monetary) As Of Credit ifrs-full:LongtermOnerousContractsProvision
94 Risk Management Concept (Monetary) As Of Credit ifrs-full:NoncurrentDerivativeFinancialLiabilities
95 Decommissioning Liabilities Concept (Monetary) As Of Credit ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCosts
96 Other Liabilities Concept (Monetary) As Of Credit ifrs-full:OtherNoncurrentLiabilities
97 Deferred Income Taxes Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
98 Total Liabilities Concept (Monetary) As Of Credit ifrs-full:Liabilities
99 Shareholders’ Equity Concept (Monetary) As Of Credit ifrs-full:Equity
100 Total Liabilities and Shareholders’ Equity Concept (Monetary) As Of Credit ifrs-full:EquityAndLiabilities
101 Commitments and Contingencies Concept (Monetary) As Of Credit cve:CommitmentsAndContingencies1
102 100040 - Statement - Consolidated Statements of Shareholders' Equity Network

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103 Statement Of Changes In Equity [Table] Table

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 ifrs-full:StatementOfChangesInEquityTable
104 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
105 Equity [member] Member ifrs-full:EquityMember
106 Share Capital [Member] Member ifrs-full:IssuedCapitalMember
107 Paid in Surplus [Member] Member ifrs-full:AdditionalPaidinCapitalMember
108 Retained Earnings [Member] Member ifrs-full:RetainedEarningsMember
109 AOCI [Member] Member ifrs-full:AccumulatedOtherComprehensiveIncomeMember
110 Statement Of Changes In Equity [Line Items] LineItems ifrs-full:StatementOfChangesInEquityLineItems
111 Beginning balance Concept (Monetary) As Of Credit ifrs-full:Equity
112 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
113 Other Comprehensive Income (Loss) Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncome
114 Comprehensive Income (Loss) Concept (Monetary) For Period Credit ifrs-full:ComprehensiveIncome
115 Common Shares Issued Concept (Monetary) For Period Credit ifrs-full:IssueOfEquity
116 Stock-Based Compensation Expense Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughSharebasedPaymentTransactions
117 Dividends on Common Shares Concept (Monetary) For Period Debit ifrs-full:DividendsPaid
118 Ending balance Concept (Monetary) As Of Credit ifrs-full:Equity
119 100050 - Statement - Consolidated Statements of Cash Flows Network

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120 Implied Table Table

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121 Statement Of Cash Flows [Abstract] Abstract ifrs-full:StatementOfCashFlowsAbstract
122 Operating Activities Abstract ifrs-full:CashFlowsFromUsedInOperatingActivitiesAbstract
123 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
124 Depreciation, Depletion and Amortization Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDepreciationAndAmortisationExpenseAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
125 Exploration Expense Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossExplorationAndEvaluationAssets
126 Deferred Income Taxes Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForDeferredTaxExpense
127 Unrealized (Gain) Loss on Risk Management Concept (Monetary) For Period Credit ifrs-full:AdjustmentsForGainsLossesOnChangeInFairValueOfDerivatives
128 Unrealized Foreign Exchange (Gain) Loss Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForUnrealisedForeignExchangeLossesGains
129 Revaluation (Gain) Concept (Monetary) For Period Debit cve:AdjustmentsForGainLossRecognisedAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
130 Re-measurement of Contingent Payment Concept (Monetary) For Period Credit cve:AdjustmentsForIncreaseDecreaseInContingentLiabilitiesRecognisedInBusinessCombination
131 (Gain) Loss on Discontinuance Concept (Monetary) For Period Credit cve:AdjustmentsForGainLossOnDiscontinuance
132 (Gain) Loss on Divestiture of Assets Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForLossesGainsOnDisposalOfNoncurrentAssets
133 Unwinding of Discount on Decommissioning Liabilities Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForFinanceCosts
134 Onerous Contract Provisions, Net of Cash Paid Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForProvisions
135 Other Asset Impairments Concept (Monetary) For Period Debit ifrs-full:AdjustmentsForImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
136 Realized Foreign Exchange (Gain) Loss on Non-Operating Items Concept (Monetary) For Period Debit cve:AdjustmentsForRealisedForeignExchangeLossesGains
137 Other Concept (Monetary) For Period Debit ifrs-full:OtherAdjustmentsForNoncashItems
138 Net Change in Other Assets and Liabilities Concept (Monetary) For Period Debit cve:AdjustmentsForIncreaseDecreaseInOtherOperatingAssetsAndLiabilities
139 Net Change in Non-Cash Working Capital Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseInWorkingCapital
140 Cash From (Used in) Operating Activities Concept (Monetary) For Period ifrs-full:CashFlowsFromUsedInOperatingActivities
141 Investing Activities Abstract ifrs-full:CashFlowsFromUsedInInvestingActivitiesAbstract
142 Acquisition, Net of Cash Acquired Concept (Monetary) For Period Credit ifrs-full:CashFlowsUsedInObtainingControlOfSubsidiariesOrOtherBusinessesClassifiedAsInvestingActivities
143 Capital Expenditures – Exploration and Evaluation Assets Concept (Monetary) For Period Credit ifrs-full:PurchaseOfExplorationAndEvaluationAssets
144 Capital Expenditures – Property, Plant and Equipment Concept (Monetary) For Period Credit ifrs-full:PurchaseOfPropertyPlantAndEquipmentClassifiedAsInvestingActivities
145 Proceeds From Divestitures Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOfOilAndGasAssets
146 Net Change in Investments and Other Concept (Monetary) For Period Debit ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsInvestingActivities
147 Net Change in Non-Cash Working Capital Concept (Monetary) For Period Debit cve:IncreaseDecreaseInWorkingCapitalClassifiedAsInvestingActivities
148 Cash From (Used in) Investing Activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInInvestingActivities
149 Net Cash Provided (Used) Before Financing Activities Concept (Monetary) For Period Debit cve:NetCashFromUsedInBeforeFinancingActivities
150 Financing Activities Abstract ifrs-full:CashFlowsFromUsedInFinancingActivitiesAbstract
151 Issuance of Long-Term Debt Concept (Monetary) For Period Debit ifrs-full:ProceedsFromNoncurrentBorrowings
152 (Repayment) of Long-Term Debt Concept (Monetary) For Period Credit ifrs-full:RepaymentsOfNoncurrentBorrowings
153 Net Issuance (Repayment) of Revolving Long-Term Debt Concept (Monetary) For Period Debit cve:CashFlowsFromUsedInIncreaseDecreaseInNonCurrentRevolvingBorrowings
154 Issuance of Debt Under Asset Sale Bridge Facility Concept (Monetary) For Period Debit cve:ProceedsFromIssuanceOfDebtUnderCommittedAssetSaleBridgeFacility
155 (Repayment) of Debt Under Asset Sale Bridge Facility Concept (Monetary) For Period Credit cve:RepaymentOfDebtUnderCommittedAssetSaleBridgeFacility
156 Common Shares Issued, Net of Issuance Costs Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssuingShares
157 Dividends Paid on Common Shares Concept (Monetary) For Period Credit ifrs-full:DividendsPaidClassifiedAsFinancingActivities
158 Other Concept (Monetary) For Period Debit ifrs-full:OtherInflowsOutflowsOfCashClassifiedAsFinancingActivities
159 Cash From (Used in) Financing Activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInFinancingActivities
160 Foreign Exchange Gain (Loss) on Cash and Cash Equivalents Held in Foreign Currency Concept (Monetary) For Period Debit ifrs-full:EffectOfExchangeRateChangesOnCashAndCashEquivalents
161 Increase (Decrease) in Cash and Cash Equivalents Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInCashAndCashEquivalents
162 Cash and Cash Equivalents, Beginning of Year Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
163 Cash and Cash Equivalents, End of Year Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
164 100060 - Disclosure - Description of Business and Segmented Disclosures Network

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165 Implied Table Table

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166 Disclosure Of Reportable Segments [Abstract] Abstract cve:DisclosureOfReportableSegmentsAbstract
167 Description of Business and Segmented Disclosures Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEntitysReportableSegmentsExplanatory
168 100070 - Disclosure - Basis of Preparation and Statement of Compliance Network

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169 Implied Table Table

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170 Basis Of Preparation And Statement Of Compliance [Abstract] Abstract cve:BasisOfPreparationAndStatementOfComplianceAbstract
171 Basis of Preparation and Statement of Compliance Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfBasisOfPreparationOfFinancialStatementsExplanatory
172 100080 - Disclosure - Summary of Significant Accounting Policies Network

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173 Implied Table Table

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174 Disclosure Of Summary Of Significant Accounting Policies [Abstract] Abstract cve:DisclosureOfSummaryOfSignificantAccountingPoliciesAbstract
175 Summary of Significant Accounting Policies Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSummaryOfSignificantAccountingPoliciesExplanatory
176 100090 - Disclosure - Changes in Accounting Policies Network

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177 Implied Table Table

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178 Disclosure Of Initial Application Of Standards Or Interpretations [Abstract] Abstract ifrs-full:DisclosureOfInitialApplicationOfStandardsOrInterpretationsAbstract
179 Changes in Accounting Policies Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfInitialApplicationOfStandardsOrInterpretations
180 100100 - Disclosure - Critical Accounting Judgments and Key Sources of Estimation Uncertainty Network

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181 Implied Table Table

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182 Disclosure Of Accounting Judgements And Estimates [Abstract] Abstract cve:DisclosureOfAccountingJudgementsAndEstimatesAbstract
183 Critical Accounting Judgments and Key Sources of Estimation Uncertainty Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAccountingJudgementsAndEstimatesExplanatory
184 100110 - Disclosure - Finance Costs Network

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185 Implied Table Table

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186 Finance Costs [Abstract] Abstract cve:FinanceCostsAbstract
187 Finance Costs Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfBorrowingCostsExplanatory
188 100120 - Disclosure - Foreign Exchange (Gain) Loss, Net Network

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189 Implied Table Table

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190 Foreign Exchange Gains Losses [Abstract] Abstract cve:ForeignExchangeGainsLossesAbstract
191 Foreign Exchange (Gain) Loss, Net Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEffectOfChangesInForeignExchangeRatesExplanatory
192 100130 - Disclosure - Divestitures Network

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193 Implied Table Table

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194 Gains Losses On Disposals Of Noncurrent Assets [Abstract] Abstract ifrs-full:GainsLossesOnDisposalsOfNoncurrentAssetsAbstract
195 Divestitures Concept (Text Block (HTML)) For Period cve:GainsLossesOnDisposalsOfNoncurrentAssetsExplanatory
196 100140 - Disclosure - Acquisition Network

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197 Implied Table Table

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198 Disclosure Of Business Combinations [Abstract] Abstract ifrs-full:DisclosureOfBusinessCombinationsAbstract
199 Acquisition Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfBusinessCombinationsExplanatory
200 100150 - Disclosure - Impairment Charges and Reversals Network

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201 Implied Table Table

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202 Disclosure Of Impairment Loss Recognised Or Reversed [Abstract] Abstract ifrs-full:DisclosureOfImpairmentLossRecognisedOrReversedAbstract
203 Impairment Charges and Reversals Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossExplanatory
204 100160 - Disclosure - Assets Held for Sale and Discontinued Operations Network

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205 Implied Table Table

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206 Disclosure Of Noncurrent Assets Held For Sale And Discontinued Operations [Abstract] Abstract cve:DisclosureOfNoncurrentAssetsHeldForSaleAndDiscontinuedOperationsAbstract
207 Assets Held for Sale and Discontinued Operations Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNoncurrentAssetsHeldForSaleAndDiscontinuedOperationsExplanatory
208 100170 - Disclosure - Income Taxes Network

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209 Implied Table Table

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210 Disclosure Of Income Tax Expense Continuing Operations [Abstract] Abstract cve:DisclosureOfIncomeTaxExpenseContinuingOperationsAbstract
211 Income Taxes Concept (Text Block (HTML)) For Period cve:DisclosureOfIncomeTaxExpenseContinuingOperationsExplanatory
212 100180 - Disclosure - Per Share Amounts Network

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213 Implied Table Table

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214 Earnings Per Share [Abstract] Abstract ifrs-full:EarningsPerShareAbstract
215 Per Share Amounts Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEarningsPerShareExplanatory
216 100190 - Disclosure - Cash and Cash Equivalents Network

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217 Implied Table Table

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218 Cash And Cash Equivalents [Abstract] Abstract ifrs-full:CashAndCashEquivalentsAbstract
219 Cash and Cash Equivalents Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCashAndCashEquivalentsExplanatory
220 100200 - Disclosure - Accounts Receivable and Accrued Revenues Network

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221 Implied Table Table

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222 Trade And Other Current Receivables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentReceivablesAbstract
223 Accounts Receivable and Accrued Revenues Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTradeAndOtherReceivablesExplanatory
224 100210 - Disclosure - Inventories Network

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225 Implied Table Table

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226 Classes Of Inventories [Abstract] Abstract ifrs-full:ClassesOfInventoriesAbstract
227 Inventories Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInventoriesExplanatory
228 100220 - Disclosure - Exploration and Evaluation Assets Network

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229 Implied Table Table

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230 Disclosure Of Exploration And Evaluation Assets [Abstract] Abstract cve:DisclosureOfExplorationAndEvaluationAssetsAbstract
231 Exploration and Evaluation Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfExplorationAndEvaluationAssetsExplanatory
232 100230 - Disclosure - Property, Plant and Equipment, Net Network

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233 Implied Table Table

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234 Disclosure Of Property Plant And Equipment [Abstract] Abstract ifrs-full:DisclosureOfPropertyPlantAndEquipmentAbstract
235 Property, Plant and Equipment, Net Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfPropertyPlantAndEquipmentExplanatory
236 100240 - Disclosure - Other Assets Network

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237 Implied Table Table

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238 Other Noncurrent Assets [Abstract] Abstract cve:OtherNoncurrentAssetsAbstract
239 Other Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherAssetsExplanatory
240 100250 - Disclosure - Goodwill Network

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241 Implied Table Table

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242 Goodwill [Abstract] Abstract cve:GoodwillAbstract
243 Goodwill Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGoodwillExplanatory
244 100260 - Disclosure - Accounts Payable and Accrued Liabilities Network

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245 Implied Table Table

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246 Trade And Other Current Payables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentPayablesAbstract
247 Accounts Payable and Accrued Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialLiabilitiesExplanatory
248 100270 - Disclosure - Long-term Debt and Capital Structure Network

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249 Implied Table Table

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250 Borrowings [Abstract] Abstract ifrs-full:BorrowingsAbstract
251 Long-term Debt and Capital Structure Concept (Text Block (HTML)) For Period cve:DisclosureOfBorrowingsAndCapitalStructureExplanatory
252 100280 - Disclosure - Contingent Payment Network

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253 Implied Table Table

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254 Disclosure Of Contingent Liabilities In Business Combination [Abstract] Abstract ifrs-full:DisclosureOfContingentLiabilitiesInBusinessCombinationAbstract
255 Contingent Payment Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfContingentLiabilitiesInBusinessCombinationExplanatory
256 100290 - Disclosure - Onerous Contract Provisions Network

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257 Implied Table Table

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258 Onerous Contracts Provision [Abstract] Abstract ifrs-full:OnerousContractsProvisionAbstract
259 Onerous Contract Provisions Concept (Text Block (HTML)) For Period cve:DisclosureOfOnerousContractProvisionsExplanatory
260 100300 - Disclosure - Decommissioning Liabilities Network

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261 Implied Table Table

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262 Provision For Decommissioning Restoration And Rehabilitation Costs [Abstract] Abstract ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCostsAbstract
263 Decommissioning Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherProvisionsContingentLiabilitiesAndContingentAssetsExplanatory
264 100310 - Disclosure - Other Liabilities Network

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265 Implied Table Table

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266 Disclosure Of Other Liabilities [Abstract] Abstract cve:DisclosureOfOtherLiabilitiesAbstract
267 Other Liabilities Concept (Text Block (HTML)) For Period cve:DisclosureOfSummaryOfOtherLiabilitiesExplanatory
268 100320 - Disclosure - Pensions and Other Post-Employment Benefits Network

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269 Implied Table Table

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270 Pension Plans [Abstract] Abstract cve:PensionPlansAbstract
271 Pensions and Other Post-Employment Benefits Concept (Text Block (HTML)) For Period cve:PensionPlansExplanatory
272 100330 - Disclosure - Share Capital Network

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273 Implied Table Table

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274 Disclosure Of Share Capital Reserves And Other Equity Interest [Abstract] Abstract cve:DisclosureOfShareCapitalReservesAndOtherEquityInterestAbstract
275 Share Capital Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfShareCapitalReservesAndOtherEquityInterestExplanatory
276 100340 - Disclosure - Accumulated Other Comprehensive Income (Loss) Network

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277 Implied Table Table

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278 Disclosure Of Accumulated Other Comprehensive Income Loss [Abstract] Abstract cve:DisclosureOfAccumulatedOtherComprehensiveIncomeLossAbstract
279 Accumulated Other Comprehensive Income (Loss) Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfAnalysisOfOtherComprehensiveIncomeByItemExplanatory
280 100350 - Disclosure - Stock-Based Compensation Plans Network

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281 Implied Table Table

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282 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Abstract] Abstract ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementAbstract
283 Stock-Based Compensation Plans Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfSharebasedPaymentArrangementsExplanatory
284 100360 - Disclosure - Employee Salaries and Benefit Expenses Network

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285 Implied Table Table

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286 Disclosure Of Salaries And Employee Benefits [Abstract] Abstract cve:DisclosureOfSalariesAndEmployeeBenefitsAbstract
287 Employee Salaries and Benefit Expenses Concept (Text Block (HTML)) For Period cve:DisclosureOfEmployeeSalariesAndBenefitExpensesExplanatory
288 100370 - Disclosure - Related Party Transactions Network

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289 Implied Table Table

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290 Disclosure Of Transactions Between Related Parties [Abstract] Abstract ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
291 Related Party Transactions Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfInformationAboutKeyManagementPersonnelExplanatory
292 100380 - Disclosure - Financial Instruments Network

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293 Implied Table Table

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294 Disclosure Of Financial Instruments [Abstract] Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
295 Financial Instruments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinancialInstrumentsExplanatory
296 100390 - Disclosure - Risk Management Network

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297 Implied Table Table

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298 Risk Management [Abstract] Abstract cve:RiskManagementAbstract
299 Risk Management Concept (Text Block (HTML)) For Period cve:DisclosureOfFinancialRiskManagementStrategyExplanatory
300 100400 - Disclosure - Supplementary Cash Flow Information Network

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301 Implied Table Table

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302 Disclosure Of Supplementary Cash Flow Information [Abstract] Abstract cve:DisclosureOfSupplementaryCashFlowInformationAbstract
303 Supplementary Cash Flow Information Concept (Text Block (HTML)) For Period cve:DisclosureOfSupplementaryCashFlowInformationExplanatory
304 100410 - Disclosure - Commitments and Contingencies Network

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305 Implied Table Table

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306 Commitments And Contingencies [Abstract] Abstract cve:CommitmentsAndContingenciesAbstract
307 Commitments and Contingencies Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCommitmentsAndContingentLiabilitiesExplanatory
308 100420 - Disclosure - Subsequent Event Network

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309 Implied Table Table

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310 Disclosure Of Nonadjusting Events After Reporting Period [Abstract] Abstract ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract
311 Subsequent Event Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEventsAfterReportingPeriodExplanatory
312 100430 - Disclosure - Summary of Significant Accounting Policies (Policies) Network

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313 Disclosure Of Summary Of Significant Accounting Policies [Table] Table

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314 New IFRSs [axis] Axis ifrs-full:NewIFRSsAxis
315 New IFRSs [member] Member ifrs-full:NewIFRSsMember
316 Adoption of IFRS 9 [Member] Member cve:IFRS9Member
317 Adoption of IFRS 15 [Member] Member cve:IFRS15Member
318 Disclosure Of Summary Of Significant Accounting Policies [Line Items] LineItems cve:DisclosureOfSummaryOfSignificantAccountingPoliciesLineItems
319 Principles of Consolidation Concept (Text Block (HTML)) For Period cve:DescriptionOfAccountingPolicyForPrinciplesOfConsolidationExplanatory
320 Foreign Currency Translation Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForForeignCurrencyTranslationExplanatory
321 Revenue Recognition Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForRecognitionOfRevenue
322 Transportation and Blending Concept (Text Block (HTML)) For Period cve:DescriptionOfAccountingPolicyForTransportationAndBlendingExpense
323 Exploration Expense Concept (Text Block (HTML)) For Period cve:DescriptionOfAccountingPolicyForExpenseArisingFromExplorationForAndEvaluationOfMineralResources
324 Employee Benefit Plans Concept (Text Block (HTML)) For Period cve:DescriptionOfAccountingPolicyForPensionPlans
325 Income Taxes Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIncomeTaxExplanatory
326 Net Earnings per Share Amounts Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForEarningsPerShareExplanatory
327 Cash and Cash Equivalents Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyToDetermineComponentsOfCashAndCashEquivalents
328 Inventories Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForMeasuringInventories
329 Exploration and Evaluation Assets Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForExplorationAndEvaluationExpenditures
330 Property, Plant and Equipment Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForPropertyPlantAndEquipmentExplanatory
331 Impairment Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForImpairmentOfAssetsExplanatory
332 Leases Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForLeasesExplanatory
333 Business Combinations and Goodwill Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForBusinessCombinationsAndGoodwillExplanatory
334 Provisions Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForProvisionsExplanatory
335 Share Capital Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForIssuedCapitalExplanatory
336 Stock-Based Compensation Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForSharebasedPaymentTransactionsExplanatory
337 Financial Instruments Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfAccountingPolicyForFinancialInstrumentsExplanatory
338 Reclassification Concept (Text Block (HTML)) For Period cve:DescriptionOfAccountingPolicyForReclassificationOfPriorYearsInformationExplanatory
339 Recent Accounting Pronouncements Concept (Text Block (HTML)) For Period ifrs-full:DescriptionOfOtherAccountingPoliciesRelevantToUnderstandingOfFinancialStatements
340 100440 - Disclosure - Description of Business and Segmented Disclosures (Tables) Network

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341 Implied Table Table

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342 Disclosure Of Reportable Segments [Abstract] Abstract cve:DisclosureOfReportableSegmentsAbstract
343 Schedule of Segment and Operational Information Concept (Text Block (HTML)) For Period cve:DisclosureOfReportableSegmentsExplanatory
344 Schedule of Revenues by Product Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfProductsAndServicesExplanatory
345 Schedule of Geographical Information Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfGeographicalAreasExplanatory
346 Schedule of Exploration and Evaluation Assets, Property, Plant and Equipment, Goodwill and Total Assets Concept (Text Block (HTML)) For Period cve:DisclosureOfAssetsByReportableSegmentsExplanatory
347 Schedule of Capital Expenditures Concept (Text Block (HTML)) For Period cve:DisclosureOfAdditionsToNoncurrentAssetsByReportableSegmentsExplanatory
348 100450 - Disclosure - Finance Costs (Tables) Network

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349 Implied Table Table

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350 Finance Costs [Abstract] Abstract cve:FinanceCostsAbstract
351 Schedule of Finance Cost Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFinanceCostExplanatory
352 100460 - Disclosure - Foreign Exchange (Gain) Loss, Net (Tables) Network

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353 Implied Table Table

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354 Foreign Exchange Gains Losses [Abstract] Abstract cve:ForeignExchangeGainsLossesAbstract
355 Schedule of Foreign Exchange Gain Loss Net Concept (Text Block (HTML)) For Period cve:DisclosureOfEffectOfChangesInForeignExchangeRatesGainLossExplanatory
356 100470 - Disclosure - Acquisition (Tables) Network

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357 Disclosure Of Business Combinations [Table] Table

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358 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
359 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
360 FCCL Partnership and Deep Basin [Member] Member cve:FCCLPartnershipAndDeepBasinMember
361 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
362 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
363 Summary of Identifiable Assets Acquired and Liabilities Assumed Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutBusinessCombinationsExplanatory
364 Summary of Fair Value of the Consideration Concept (Text Block (HTML)) For Period cve:FairValueOfConsiderationExplanatory
365 Summary of Goodwill arising from Acquisition Concept (Text Block (HTML)) For Period cve:AdditionalRecognitionOfGoodwillExplanatory
366 100480 - Disclosure - Impairment Charges and Reversals (Tables) Network

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367 Implied Table Table

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368 Disclosure Of Impairment Loss Recognised Or Reversed [Abstract] Abstract ifrs-full:DisclosureOfImpairmentLossRecognisedOrReversedAbstract
369 Summary of Forward Prices Used to Determine Future Cash Flows Concept (Text Block (HTML)) For Period cve:DisclosureOfKeyAssumptionsOnWhichManagementHasBasedCashFlowProjectionsExplanatory
370 100490 - Disclosure - Assets Held for Sale and Discontinued Operations (Tables) Network

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371 Implied Table Table

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372 Disclosure Of Noncurrent Assets Held For Sale And Discontinued Operations [Abstract] Abstract cve:DisclosureOfNoncurrentAssetsHeldForSaleAndDiscontinuedOperationsAbstract
373 Summary of Assets and Liabilities Held for Sale Concept (Text Block (HTML)) For Period cve:DisclosureOfNoncurrentAssetsAndLiabilitiesHeldForSaleExplanatory
374 Results of Discontinued Operations Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDiscontinuedOperationsExplanatory
375 Summary of Cash Flows from Discontinued Operations Concept (Text Block (HTML)) For Period cve:DisclosureOfIncreaseDecreaseInCashAndCashEquivalentsDiscontinuedOperationsExplanatory
376 100500 - Disclosure - Income Taxes (Tables) Network

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377 Implied Table Table

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378 Disclosure Of Income Taxes Continuing Operations [Abstract] Abstract cve:DisclosureOfIncomeTaxesContinuingOperationsAbstract
379 Provision for Income Taxes Concept (Text Block (HTML)) For Period cve:DisclosureOfComponentsOfIncomeTaxExpenseContinuingOperationsExplanatory
380 Reconciliation of Income Taxes Calculated at Statutory Rate Concept (Text Block (HTML)) For Period cve:DisclosureOfReconciliationOfAccountingProfitFromContinuingOperationsMultipliedByApplicableTaxRatesExplanatory
381 Deferred Income Tax Liabilities and Deferred Income Tax Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDeferredTaxesExplanatory
382 Schedule of Movement in Deferred Income Tax Liabilities and Assets Concept (Text Block (HTML)) For Period cve:DisclosureOfReconciliationOfChangesInDeferredTaxLiabilityAssetExplanatory
383 Schedule of Amounts of Tax Pools Available, Including Tax Losses Concept (Text Block (HTML)) For Period cve:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCredits
384 100510 - Disclosure - Per Share Amounts (Tables) Network

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385 Implied Table Table

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386 Earnings Per Share [Abstract] Abstract ifrs-full:EarningsPerShareAbstract
387 Schedule Representing Per Share Amounts Concept (Text Block (HTML)) For Period ifrs-full:EarningsPerShareExplanatory
388 100520 - Disclosure - Cash and Cash Equivalents (Tables) Network

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389 Implied Table Table

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390 Cash And Cash Equivalents [Abstract] Abstract ifrs-full:CashAndCashEquivalentsAbstract
391 Disclosure Of Cash And Cash Equivalent Explanatory Concept (Text Block (HTML)) For Period cve:DisclosureOfCashAndCashEquivalentExplanatory
392 100530 - Disclosure - Accounts Receivable and Accrued Revenues (Tables) Network

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393 Implied Table Table

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394 Trade And Other Current Receivables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentReceivablesAbstract
395 Schedule of Accounts Receivable and Accrued Revenues Concept (Text Block (HTML)) For Period cve:DisclosureOfDetailedInformationAboutTradeAndOtherReceivablesExplanatory
396 100540 - Disclosure - Inventories (Tables) Network

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397 Implied Table Table

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398 Classes Of Inventories [Abstract] Abstract ifrs-full:ClassesOfInventoriesAbstract
399 Disclosure Of Detailed Information About Inventories Explanatory Concept (Text Block (HTML)) For Period cve:DisclosureOfDetailedInformationAboutInventoriesExplanatory
400 100550 - Disclosure - Exploration and Evaluation Assets (Tables) Network

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401 Implied Table Table

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402 Disclosure Of Exploration And Evaluation Assets [Abstract] Abstract cve:DisclosureOfExplorationAndEvaluationAssetsAbstract
403 Summary of Exploration and Valuation Assets Concept (Text Block (HTML)) For Period cve:DisclosureOfChangesInExplorationAndEvaluationAssetsExplanatory
404 100560 - Disclosure - Property, Plant and Equipment, Net (Tables) Network

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405 Implied Table Table

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406 Disclosure Of Property Plant And Equipment [Abstract] Abstract ifrs-full:DisclosureOfPropertyPlantAndEquipmentAbstract
407 Summary of Property, Plant and Equipment Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutPropertyPlantAndEquipmentExplanatory
408 Summary of PP&E Under Construction and Not Subject to DD&A Concept (Text Block (HTML)) For Period cve:DisclosureOfPropertyPlantAndEquipmentUnderConstructionExplanatory
409 100570 - Disclosure - Other Assets (Tables) Network

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410 Implied Table Table

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411 Other Noncurrent Assets [Abstract] Abstract cve:OtherNoncurrentAssetsAbstract
412 Summary of Other Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherNoncurrentAssetsExplanatory
413 100580 - Disclosure - Goodwill (Tables) Network

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414 Implied Table Table

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415 Goodwill [Abstract] Abstract cve:GoodwillAbstract
416 Summary of Carrying Value of Goodwill Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillExplanatory
417 100590 - Disclosure - Accounts Payable and Accrued Liabilities (Tables) Network

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418 Implied Table Table

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419 Trade And Other Current Payables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentPayablesAbstract
420 Schedule of Accounts Payable and Accrued Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTradeAndOtherPayablesExplanatory
421 100600 - Disclosure - Long-term Debt and Capital Structure (Tables) Network

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422 Implied Table Table

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423 Borrowings [Abstract] Abstract ifrs-full:BorrowingsAbstract
424 Schedule of Long Term Debt Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsExplanatory
425 Schedule Of Unsecured Notes Explanatory Concept (Text Block (HTML)) For Period cve:ScheduleOfUnsecuredNotesExplanatory
426 Schedule of Mandatory Debt Payments Concept (Text Block (HTML)) For Period ifrs-full:MaturityAnalysisForNonderivativeFinancialLiabilities
427 Summary of Net Debt to Adjusted EBITDA Concept (Text Block (HTML)) For Period cve:DisclosureOfNetDebtToAdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortizationExplanatory
428 Summary of Net Debt to Capitalization Concept (Text Block (HTML)) For Period cve:DisclosureOfNetDebtToCapitalizationExplanatory
429 100610 - Disclosure - Contingent Payment (Tables) Network

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430 Implied Table Table

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431 Disclosure Of Contingent Liabilities In Business Combination [Abstract] Abstract ifrs-full:DisclosureOfContingentLiabilitiesInBusinessCombinationAbstract
432 Summary of Contingent Payment Concept (Text Block (HTML)) For Period cve:DisclosureOfReconciliationOfChangesInFairValueMeasurementOfContingentConsiderationExplanatory
433 100620 - Disclosure - Onerous Contract Provisions (Tables) Network

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434 Implied Table Table

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435 Onerous Contracts Provision [Abstract] Abstract ifrs-full:OnerousContractsProvisionAbstract
436 Summary of Onerous Contract Provisions Concept (Text Block (HTML)) For Period cve:DisclosureOfContractProvisionsExplanatory
437 Summary of Changes to Credit Adjusted Risk Free Rate or Estimated Sublease Recovery on Onerous Contract Provisions Concept (Text Block (HTML)) For Period cve:DisclosureOfChangesCreditAdjustedRiskFreeRateOrEstimatedSubleaseRecoveriesExplanatory
438 100630 - Disclosure - Decommissioning Liabilities (Tables) Network

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439 Implied Table Table

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440 Provision For Decommissioning Restoration And Rehabilitation Costs [Abstract] Abstract ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCostsAbstract
441 Summary of Decommissioning Provision Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherProvisionsExplanatory
442 Summary of Changes to the Credit-Adjusted Risk-Free Rate or the Inflation Rate Impact on the Decommissioning Liabilities Concept (Text Block (HTML)) For Period cve:DescriptionOfMajorAssumptionsMadeConcerningFutureEventsOtherProvisionsExplanatory
443 100640 - Disclosure - Other Liabilities (Tables) Network

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444 Implied Table Table

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445 Disclosure Of Other Liabilities [Abstract] Abstract cve:DisclosureOfOtherLiabilitiesAbstract
446 Summary of Other Liabilities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOtherLiabilitiesExplanatory
447 100650 - Disclosure - Pensions and Other Post-Employment Benefits (Tables) Network

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448 Implied Table Table

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449 Pension Plans [Abstract] Abstract cve:PensionPlansAbstract
450 Summary of Defined Benefit and OPEB Plan Obligation and Funded Status Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetExplanatory
451 Summary of Pension and OPEB Costs Concept (Text Block (HTML)) For Period cve:DisclosureOfDefinedBenefitPlanCostExplanatory
452 Summary of Fair Value of the Plan Assets Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfFairValueOfPlanAssetsExplanatory
453 Summary of principal weighted average actuarial assumptions used to determine benefit obligations and expenses Concept (Text Block (HTML)) For Period cve:DisclosureOfActuarialAssumptionsExplanatory
454 Sensitivity of defined benefit and OPEB obligation to changes in relevant actuarial assumptions Concept (Text Block (HTML)) For Period cve:DisclosureOfSensitivityAnalysisForActuarialAssumptionsOfDefinedBenefitAndOtherPostEmploymentBenefitsObligationExplanatory
455 100660 - Disclosure - Share Capital (Tables) Network

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456 Implied Table Table

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457 Disclosure Of Classes Of Share Capital [Abstract] Abstract ifrs-full:DisclosureOfClassesOfShareCapitalAbstract
458 Summary of Share Capital Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfClassesOfShareCapitalExplanatory
459 Disclosure Of Paid In Surplus Includes Stock Based Compensation Expense Explanatory Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReservesAndOtherEquityInterestExplanatory
460 100670 - Disclosure - Accumulated Other Comprehensive Income (Loss) (Tables) Network

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461 Implied Table Table

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462 Disclosure Of Accumulated Other Comprehensive Income Loss [Abstract] Abstract cve:DisclosureOfAccumulatedOtherComprehensiveIncomeLossAbstract
463 Summary of Accumulated Other Comprehensive Income (Loss) Concept (Text Block (HTML)) For Period cve:DisclosureOfAccumulatedOtherComprehensiveIncomeLossExplanatory
464 100680 - Disclosure - Stock-Based Compensation Plans (Tables) Network

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465 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table] Table

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466 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
467 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
468 NSRs [Member] Member cve:NetSettlementRightsMember
469 PSUs [Member] Member cve:PerformanceShareUnitsMember
470 RSUs [Member] Member cve:RestrictedShareUnitMember
471 DSUs [Member] Member cve:DeferredShareUnitsMember
472 Disclosure of terms and conditions of share-based payment arrangement [Line Items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
473 Summary of Assumptions Used to Determine Fair Value of Options Granted Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfIndirectMeasurementOfFairValueOfGoodsOrServicesReceivedShareOptionsGrantedDuringPeriodExplanatory
474 Summary of Units Activity and Related Information Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNumberAndWeightedAverageExercisePricesOfOtherEquityInstrumentsExplanatory
475 Summary of Options Outstanding and Exercisable by Range of Exercise Price Concept (Text Block (HTML)) For Period cve:DisclosureOfOptionsOutstandingAndExercisableAndWeightedAveragePriceOptionsExplanatory
476 Summary of Stock-Based Compensation Concept (Text Block (HTML)) For Period cve:ExplanationOfEffectOfShareBasedPaymentsOnProfitOrLossAndFinancialPositionsExplanatory
477 100690 - Disclosure - Employee Salaries and Benefit Expenses (Tables) Network

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478 Implied Table Table

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479 Disclosure Of Salaries And Employee Benefits [Abstract] Abstract cve:DisclosureOfSalariesAndEmployeeBenefitsAbstract
480 Summary of Employee Salaries and Benefit Expenses Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfEmployeeBenefitsExplanatory
481 100700 - Disclosure - Related Party Transactions (Tables) Network

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482 Disclosure Of Transactions Between Related Parties [Table] Table

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483 Categories of related parties [axis] Axis ifrs-full:CategoriesOfRelatedPartiesAxis
484 Entity's total for related parties [member] Member ifrs-full:EntitysTotalForRelatedPartiesMember
485 Key Management Personnel of Entity or Parent [Member] Member ifrs-full:KeyManagementPersonnelOfEntityOrParentMember
486 Disclosure Of Transactions Between Related Parties [Line Items] LineItems ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesLineItems
487 Summary of Key Management Compensation Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesExplanatory
488 100710 - Disclosure - Financial Instruments (Tables) Network

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489 Implied Table Table

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490 Disclosure Of Financial Instruments [Abstract] Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
491 Reconciliation of Changes in the Fair Value of Available for Sale Financial Assets Concept (Text Block (HTML)) For Period cve:DisclosureOfReconciliationOfChangesInFairValueMeasurementOfAssetsExplanatory
492 Summary of Unrealized Risk Management Positions Concept (Text Block (HTML)) For Period cve:DisclosureOfFairValueMeasurementOfAssetsLiabilitiesExplanatory
493 Summary of Fair Value Hierarchy for Risk Management Assets and Liabilities Carried at Fair Value Concept (Text Block (HTML)) For Period cve:DisclosureOfLevelsOfFairValueHierarchyExplanatory
494 Reconciliation of Changes in the Fair Value of Cenovus's Risk Management Assets and Liabilities Concept (Text Block (HTML)) For Period cve:DisclosureOfReconciliationOfChangesInFairValueMeasurementAssetsLiabilitiesExplanatory
495 Summary of Offsetting Risk Management Positions Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfOffsettingOfFinancialAssetsAndFinancialLiabilitiesExplanatory
496 Summary of Changes in Inputs to Option Pricing Model, Resulted in Unrealized Gains (Losses) Impacting Earnings Before Income Tax Concept (Text Block (HTML)) For Period ifrs-full:SensitivityAnalysisForEachTypeOfMarketRisk
497 Summary of Earnings Impact of (Gains) Losses from Risk Management Positions Concept (Text Block (HTML)) For Period cve:DisclosureOfGainsLossesOnChangeInFairValueOfDerivativesExplanatory
498 100720 - Disclosure - Risk Management (Tables) Network

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499 Disclosure Of Derivative Financial Instruments [Table] Table

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501 Risks [member] Member ifrs-full:TypesOfRisksMember
502 Commodity Price Risk [Member] Member ifrs-full:CommodityPriceRiskMember
503 Currency risk [Member] Member ifrs-full:CurrencyRiskMember
504 Interest Rate Risk [Member] Member ifrs-full:InterestRateRiskMember
505 Disclosure of Derivative Financial Instruments [Line Items] LineItems cve:DisclosureOfDerivativeFinancialInstrumentsLineItems
506 Net Fair Value of Risk Management Positions Concept (Text Block (HTML)) For Period cve:DisclosureOfFairValueOfDerivativeFinancialInstrumentsNetExplanatory
507 Summary of Changes in Inputs to Option Pricing Model, Resulted in Unrealized Gains (Losses) Impacting Earnings Before Income Tax Concept (Text Block (HTML)) For Period ifrs-full:SensitivityAnalysisForEachTypeOfMarketRisk
508 Undiscounted Cash Outflows Relating to Financial Liabilities Concept (Text Block (HTML)) For Period cve:DisclosureOfMaturityAnalysisForDerivativeAndNonDerivativeFinancialLiabilitiesExplanatory
509 100730 - Disclosure - Supplementary Cash Flow Information (Tables) Network

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510 Implied Table Table

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511 Disclosure Of Supplementary Cash Flow Information [Abstract] Abstract cve:DisclosureOfSupplementaryCashFlowInformationAbstract
512 Disclosure Of Supplementary Cash Flow Information Explanatory Text Block Concept (Text Block (HTML)) For Period cve:DisclosureOfSupplementaryCashFlowInformationExplanatoryTextBlock
513 Summary of Reconciliation of Cash Flows from Financing Activities Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesExplanatory
514 100740 - Disclosure - Commitments and Contingencies (Tables) Network

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515 Implied Table Table

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516 Commitments And Contingencies [Abstract] Abstract cve:CommitmentsAndContingenciesAbstract
517 Summary of Future Payments of Commitments Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfCommitmentsExplanatory
518 100750 - Disclosure - Subsequent Event (Tables) Network

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519 Implied Table Table

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520 Disclosure Of Nonadjusting Events After Reporting Period [Abstract] Abstract ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodAbstract
521 Summary of Remaining Principal Amount of Unsecured Notes Concept (Text Block (HTML)) For Period ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodExplanatory
522 100760 - Disclosure - Description of Business and Segmented Disclosures - Additional Information (Detail) Network

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523 Disclosure Of Operating Segments [Table] Table

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525 Segments [member] Member ifrs-full:SegmentsMember
526 Deep Basin [Member] Member cve:DeepBasinSegmentMember
527 Refining and Marketing [Member] Member cve:RefiningAndMarketingSegmentMember
528 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
529 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
530 Canada [Member] Member country:CA
531 Range [axis] Axis ifrs-full:RangeAxis
532 Ranges [member] Member ifrs-full:RangesMember
533 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
534 Top of range [Member] Member ifrs-full:TopOfRangeMember
535 Major customers [axis] Axis ifrs-full:MajorCustomersAxis
536 Customers [member] Member ifrs-full:MajorCustomersMember
537 Customer One [Member] Member cve:CustomerOneMember
538 Customer Two [Member] Member cve:CustomerTwoMember
539 Customer Three [Member] Member cve:CustomerThreeMember
540 Disclosure Of Operating Segments [Line Items] LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
541 Acres of land Concept (num:areaItemType) For Period cve:AcresOfLandAcquiredInBusinessCombination
542 Number of refineries Concept (Integer) For Period cve:NumberOfRefineries
543 Sales of crude oil, natural gas and NGLs Concept (Monetary) For Period Credit cve:ExportSalesOfOilAndGasProductsFromForeignLocation
544 Number of major customers Concept (Integer) For Period cve:NumberOfMajorCustomers
545 Percentage of entity's revenue from gross sales Concept (Percent) For Period cve:PercentageOfEntitiesRevenuesFromGrossSales
546 Gross Sales Concept (Monetary) For Period Credit cve:RevenueFromGrossSales
547 100770 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Segment and Operational Information (Detail) Network

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548 Disclosure Of Operating Segments [Table] Table

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551 Oil Sands [Member] Member cve:OilSandsSegmentMember
552 Deep Basin [Member] Member cve:DeepBasinSegmentMember
553 Refining and Marketing [Member] Member cve:RefiningAndMarketingSegmentMember
554 Corporate and Eliminations [Member] Member cve:CorporateAndEliminationsSegmentMember
555 Disclosure Of Operating Segments [Line Items] LineItems ifrs-full:DisclosureOfOperatingSegmentsLineItems
556 Revenues Abstract ifrs-full:RevenueAbstract
557 Gross Sales Concept (Monetary) For Period Credit cve:RevenueFromGrossSales
558 Less: Royalties Concept (Monetary) For Period Debit ifrs-full:RoyaltyExpense
559 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
560 Expenses Abstract ifrs-full:MaterialIncomeAndExpenseAbstract
561 Purchased Product Concept (Monetary) For Period Debit ifrs-full:RawMaterialsAndConsumablesUsed
562 Transportation and Blending Concept (Monetary) For Period Debit cve:TransportationAndBlendingExpense
563 Operating Concept (Monetary) For Period Debit ifrs-full:OperatingExpense
564 Production and Mineral Taxes Concept (Monetary) For Period Debit cve:ProductionAndMineralTaxes
565 (Gain) Loss on Risk Management Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnChangeInFairValueOfDerivatives
566 Operating Margin Concept (Monetary) For Period Credit cve:OperatingMargin
567 Depreciation, Depletion and Amortization Concept (Monetary) For Period Debit ifrs-full:DepreciationAmortisationAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
568 Exploration Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseArisingFromExplorationForAndEvaluationOfMineralResources
569 Segment Income (Loss) Concept (Monetary) For Period Credit cve:ReportableSegmentProfitLoss
570 General and Administrative Concept (Monetary) For Period Debit ifrs-full:GeneralAndAdministrativeExpense
571 Onerous Contract Provisions Concept (Monetary) For Period Debit cve:OnerousContractExpense
572 Finance Costs Concept (Monetary) For Period Debit ifrs-full:FinanceCosts
573 Interest Income Concept (Monetary) For Period Credit ifrs-full:FinanceIncome
574 Foreign Exchange (Gain) Loss, Net Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
575 Revaluation (Gain) Concept (Monetary) For Period Credit cve:RevaluationGain
576 Transaction Costs Concept (Monetary) For Period Debit cve:TransactionCosts
577 Re-measurement of Contingent Payment Concept (Monetary) For Period Debit cve:RemeasurementOfContingentPayment
578 Research Costs Concept (Monetary) For Period Debit ifrs-full:ResearchAndDevelopmentExpense
579 (Gain) Loss on Divestiture of Assets Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnDisposalsOfNoncurrentAssets
580 Other (Income) Loss, Net Concept (Monetary) For Period Credit ifrs-full:OtherGainsLosses
581 Total Non-operating (Income) Expense Concept (Monetary) For Period Credit cve:CorporateAndEliminationsReportableSegmentCosts
582 Earnings (Loss) From Continuing Operations Before Income Tax Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTax
583 Income Tax Expense (Recovery) Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
584 Net Earnings (Loss) From Continuing Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromContinuingOperations
585 100780 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Revenues by Product (Detail) Network

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586 Disclosure Of Reportable Segments [Table] Table

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587 Products and services [axis] Axis ifrs-full:ProductsAndServicesAxis
588 Products and services [member] Member ifrs-full:ProductsAndServicesMember
589 Upstream Member cve:UpstreamMember
590 Disclosure Of Reportable Segments [Line Items] LineItems cve:DisclosureOfReportableSegmentsLineItems
591 Crude Oil Concept (Monetary) For Period Credit ifrs-full:RevenueFromSaleOfCrudeOil
592 Natural Gas Concept (Monetary) For Period Credit ifrs-full:RevenueFromSaleOfNaturalGas
593 NGLs Concept (Monetary) For Period Credit cve:RevenueFromSaleOfNaturalGasLiquids
594 Other Concept (Monetary) For Period Credit cve:RevenueFromSaleOfOtherUpstreamProducts
595 Refined Product Concept (Monetary) For Period Credit ifrs-full:RevenueFromSaleOfPetroleumAndPetrochemicalProducts
596 Market Optimization Concept (Monetary) For Period Credit cve:RevenueFromMarketOptimizationActivities
597 Corporate and Eliminations Concept (Monetary) For Period Credit cve:EliminationOfIntersegmentRevenue
598 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
599 100790 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Geographical Information (Detail) Network

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600 Disclosure Of Geographical Areas [Table] Table

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601 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
602 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
603 Canada [Member] Member cve:CanadaMember
604 United States [Member] Member cve:UnitedStatesMember
605 Disclosure Of Geographical Areas [Line Items] LineItems ifrs-full:DisclosureOfGeographicalAreasLineItems
606 Revenue Concept (Monetary) For Period Credit ifrs-full:Revenue
607 Non-Current Assets Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsOtherThanFinancialInstrumentsDeferredTaxAssetsPostemploymentBenefitAssetsAndRightsArisingUnderInsuranceContracts
608 100800 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Exploration and Evaluation Assets, Property, Plant and Equipment, Goodwill and Total Assets (Detail) Network

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609 Disclosure Of Reportable Segments [Table] Table

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610 Segments [axis] Axis ifrs-full:SegmentsAxis
611 Segments [member] Member ifrs-full:SegmentsMember
612 Oil Sands [Member] Member cve:OilSandsSegmentMember
613 Deep Basin [Member] Member cve:DeepBasinSegmentMember
614 Refining and Marketing [Member] Member cve:RefiningAndMarketingSegmentMember
615 Corporate and Eliminations [Member] Member cve:CorporateAndEliminationsSegmentMember
616 Conventional [Member] Member cve:ConventionalSegmentMember
617 Disclosure Of Reportable Segments [Line Items] LineItems cve:DisclosureOfReportableSegmentsLineItems
618 E&E Assets Concept (Monetary) As Of Debit ifrs-full:IntangibleExplorationAndEvaluationAssets
619 PP&E Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
620 Goodwill Concept (Monetary) As Of Debit ifrs-full:Goodwill
621 Total Assets Concept (Monetary) As Of Debit ifrs-full:Assets
622 100810 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Capital Expenditures (Detail) Network

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623 Disclosure Of Reportable Segments [Table] Table

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624 Segments [axis] Axis ifrs-full:SegmentsAxis
625 Segments [member] Member ifrs-full:SegmentsMember
626 Oil Sands Segment [Member] Member cve:OilSandsSegmentMember
627 Deep Basin Segment [Member] Member cve:DeepBasinMember
628 Conventional Segment [Member] Member cve:ConventionalSegmentMember
629 Refining and Marketing Segment [Member] Member cve:RefiningAndMarketingSegmentMember
630 Corporate and Eliminations Segment [member] Member cve:CorporateAndEliminationsSegmentMember
631 Disclosure Of Reportable Segments [Line Items] LineItems cve:DisclosureOfReportableSegmentsLineItems
632 Capital Investment Concept (Monetary) For Period Debit cve:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipmentAndExplorationAndEvaluationAssets
633 Capital Investment Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
634 Acquisition Capital Concept (Monetary) For Period Debit cve:AcquisitionsThroughBusinessCombinationsPropertyPlantAndEquipmentAndAcquisitionsOfExplorationAndEvaluationAssets
635 Total Capital Expenditures Concept (Monetary) For Period Debit ifrs-full:AdditionsToNoncurrentAssets
636 100820 - Disclosure - Description of Business and Segmented Disclosures - Schedule of Capital Expenditures (Parenthetical) (Detail) Network

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637 Implied Table Table

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638 Disclosure Of Business Combinations [Abstract] Abstract ifrs-full:DisclosureOfBusinessCombinationsAbstract
639 Carrying value of pre-existing interest Concept (Monetary) For Period Debit cve:AcquisitionDateCarryingValueOfFCCLPropertyPlantAndEquipmentNetAndExplorationAndEvaluationAssets
640 Estimated fair value Concept (Monetary) For Period Debit cve:AcquisitionDateFairValueOfPropertyPlantAndEquipmentNetAndExplorationAndEvaluationAssets
641 100830 - Disclosure - Summary of Significant Accounting Policies - Additional information (Detail) Network

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642 Disclosure Of Summary Of Significant Accounting Policies [Table] Table

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643 Range [axis] Axis ifrs-full:RangeAxis
644 Ranges [member] Member ifrs-full:RangesMember
645 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
646 Top of range [Member] Member ifrs-full:TopOfRangeMember
647 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
648 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
649 Other Upstream Assets [Member] Member cve:OtherUpstreamAssetsMember
650 Land Improvements and Buildings [Member] Member cve:LandImprovementsAndBuildingsMember
651 Office Equipment and Vehicles [Member] Member cve:OfficeEquipmentAndVehiclesMember
652 Refining Equipment [Member] Member cve:RefiningEquipmentsMember
653 Other [Member] Member ifrs-full:OtherPropertyPlantAndEquipmentMember
654 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
655 Assets [member] Member ifrs-full:ClassesOfAssetsMember
656 Refining Assets [Member] Member cve:RefiningAssetsMember
657 Disclosure Of Summary Of Significant Accounting Policies [Line Items] LineItems cve:DisclosureOfSummaryOfSignificantAccountingPoliciesLineItems
658 Term of payments due date upon revenue recognition Concept (Text/String) For Period cve:DescriptionOfCollectionTermsInContractsWithCustomers
659 Description of payment terms Concept (Text/String) For Period ifrs-full:DescriptionOfSignificantPaymentTermsInContractsWithCustomers
660 Useful lives of assets Concept (xbrli:durationItemType) For Period cve:UsefulLivesOrDepreciationRatesOfPropertyPlantAndEquipment
661 Additional lease liabilities Concept (Monetary) As Of Credit ifrs-full:FinanceLeaseLiabilities
662 ROU Asset Concept (Monetary) As Of Debit cve:RightOfUseAsset
663 Investment leases net Concept (Monetary) For Period Credit cve:InvestmentLeasesNet
664 100840 - Disclosure - Critical Accounting Judgments and Key Sources of Estimation Uncertainty - Additional Information (Detail) Network

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665 Disclosure Of Joint Operations [Table] Table

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666 Joint operations [axis] Axis ifrs-full:JointOperationsAxis
667 Entity's total for joint operations [member] Member ifrs-full:EntitysTotalForJointOperationsMember
668 WRB [Member] Member cve:WRBRefiningLPMember
669 FCCL [Member] Member cve:FCCLPartnershipMember
670 Disclosure Of Joint Operations [Line Items] LineItems ifrs-full:DisclosureOfJointOperationsLineItems
671 Percent of ownership in joint operations Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestInJointOperation
672 Number of joint operations Concept (Integer) For Period cve:NumberOfJointOperationsPartnerships
673 100850 - Disclosure - Finance Costs - Schedule of Finance Costs (Detail) Network

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674 Implied Table Table

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675 Finance Costs [Abstract] Abstract cve:FinanceCostsAbstract
676 Interest Expense – Short-Term Borrowings and Long-Term Debt Concept (Monetary) For Period Debit ifrs-full:InterestExpenseOnBorrowings
677 Premium (Discount) on Redemption of Long-Term Debt (Note 22) Concept (Monetary) For Period Debit cve:PremiumDiscountOnRedemptionOfLongTermDebt
678 Unwinding of Discount on Decommissioning Liabilities Concept (Monetary) For Period Debit ifrs-full:ExpenseDueToUnwindingOfDiscountOnProvisions
679 Other Concept (Monetary) For Period Debit ifrs-full:OtherFinanceCost
680 Total Concept (Monetary) For Period Debit ifrs-full:FinanceCosts
681 100860 - Disclosure - Foreign Exchange (Gain) Loss, Net - Schedule of Foreign Exchange Gain Loss Net (Detail) Network

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682 Disclosure Of Effect Of Changes In Foreign Exchange Rates Gain Loss [Table] Table

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683 Classes of liabilities [axis] Axis ifrs-full:ClassesOfLiabilitiesAxis
684 Liabilities [member] Member ifrs-full:LiabilitiesMember
685 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
686 Other [Member] Member cve:OthersMember
687 Disclosure Of Effect Of Changes In Foreign Exchange Rates Gain Loss [Line Items] LineItems cve:DisclosureOfEffectOfChangesInForeignExchangeRatesGainLossLineItems
688 Foreign Exchange Gains Losses: Abstract cve:ForeignExchangeGainsLossesAbstract
689 Unrealized Foreign Exchange (Gain) Loss Concept (Monetary) For Period Credit cve:UnrealizedForeignExchangeGainLoss
690 Realized Foreign Exchange (Gain) Loss Concept (Monetary) For Period Credit cve:RealizedForeignExchangeGainLoss
691 Total Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
692 100870 - Disclosure - Divestitures - Additional Information (Detail) Network

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693 Disclosure Of Disposals [Table] Table

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694 Continuing and discontinued operations [axis] Axis ifrs-full:ContinuingAndDiscontinuedOperationsAxis
695 Aggregate continuing and discontinued operations [member] Member ifrs-full:AggregateContinuingAndDiscontinuedOperationsMember
696 Cenovus Pipestone Partnership [Member] Member cve:CenovusPipestonePartnershipMember
697 Wembley Gas Plant [Member] Member cve:WembleyGasPlantMember
698 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
699 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
700 Land [Member] Member ifrs-full:LandMember
701 Other [Member] Member ifrs-full:OtherPropertyPlantAndEquipmentMember
702 Disclosure Of Disposals [Line Items] LineItems cve:DisclosureOfDisposalsLineItems
703 Proceeds From Divestiture of Assets Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOfOilAndGasAssets
704 Percentage of operating working capital interest Concept (Percent) As Of cve:PercentageOfOperatingWorkingCapitalInterest
705 Gain (Loss) before tax on sale of assets Concept (Monetary) For Period Debit cve:GainsLossesOnSalesOfAssetsBeforeTax
706 Gain (Loss) after tax on sale of assets Concept (Monetary) For Period Debit cve:GainsLossesOnSalesOfAssetsAfterTax
707 Gains losses on disposals of property plant and equipment Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnDisposalsOfPropertyPlantAndEquipment
708 100880 - Disclosure - Acquisition - Additional Information (Detail) Network

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709 Disclosure Of Business Combinations [Table] Table

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710 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
711 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
712 FCCL [Member] Member cve:FCCLPartnershipMember
713 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
714 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
715 Percentage of voting equity interests acquired Concept (Percent) As Of ifrs-full:PercentageOfVotingEquityInterestsAcquired
716 Description of acquiree Concept (Text/String) For Period ifrs-full:DescriptionOfAcquiree
717 Cash transferred from cash and cash equivalents Concept (Monetary) As Of Credit cve:CashTransferredFromCashAndCashEquivalents
718 Consideration transferred as common shares Concept (Decimal) As Of ifrs-full:NumberOfInstrumentsOrInterestsIssuedOrIssuable
719 Contingent payments period Concept (Text/String) For Period ifrs-full:DescriptionOfExpectedTimingOfOutflowsContingentLiabilitiesInBusinessCombination
720 Common stock price per share Concept (Share) As Of cve:FairValueOfInstrumentsOrInterestsIssuedOrIssuable
721 Borrowings Concept (Monetary) As Of Credit ifrs-full:Borrowings
722 Average crude oil price per barrel Concept (Decimal) For Period cve:AverageCrudeOilPricePerBarrel
723 Quarterly contingent payment Concept (Monetary) For Period Credit cve:EstimatedQuarterlyContingentPaymentBusinessCombination
724 Estimated contingent payment Concept (Monetary) As Of Credit cve:NewLiabilitiesContingentLiabilitiesRecognizedInBusinessCombination
725 Credit-adjusted risk-free rate Concept (Percent) For Period cve:CreditAdjustedRiskFreeRate
726 Fair Value of Pre-Existing 50 Percent Ownership Interest in FCCL Concept (Monetary) As Of Credit ifrs-full:AcquisitiondateFairValueOfEquityInterestInAcquireeHeldByAcquirerImmediatelyBeforeAcquisitionDate
727 Carrying value of assets Concept (Monetary) As Of Debit cve:AcquisitionDateCarryingValueOfNetAssets
728 Non-cash revaluation (gain) Concept (Monetary) For Period Credit ifrs-full:GainLossRecognisedAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
729 Non-cash revaluation, after -tax Concept (Monetary) For Period Credit cve:GainLossRecognisedAfterTaxAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
730 Acquisition-related costs, excluding common share and debt issuance costs Concept (Monetary) For Period Debit ifrs-full:AcquisitionrelatedCostsRecognisedAsExpenseForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
731 Debt issuance costs related to acquisition financing Concept (Monetary) As Of Credit cve:DebtIssuanceCostsRelatedToAcquisitionFinancing
732 Transition services agreement period Concept (Text/String) For Period ifrs-full:ExplanationOfTransactionsRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
733 Acquisition related costs, transitional services agreement Concept (Monetary) For Period ifrs-full:AmountsRecognisedForTransactionRecognisedSeparatelyFromAcquisitionOfAssetsAndAssumptionOfLiabilitiesInBusinessCombination
734 Revenue Concept (Monetary) For Period Credit ifrs-full:RevenueOfAcquiree
735 Net earnings Concept (Monetary) For Period Credit ifrs-full:ProfitLossOfAcquiree
736 Proforma revenue Concept (Monetary) For Period Credit ifrs-full:RevenueOfCombinedEntity
737 Proforma net earnings Concept (Monetary) For Period Credit ifrs-full:ProfitLossOfCombinedEntity
738 100890 - Disclosure - Acquisition - Summary of Identifiable Assets Acquired and Liabilities Assumed (Detail) Network

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739 Disclosure Of Business Combinations [Table] Table

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740 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
741 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
742 FCCL [Member] Member cve:FCCLPartnershipMember
743 Deep Basin [Member] Member cve:DeepBasinMember
744 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
745 Cash Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalentsRecognisedAsOfAcquisitionDate
746 Accounts Receivable and Accrued Revenues Concept (Monetary) As Of Debit cve:TradeAndOtherReceivablesRecognizedAsOfAcquisitionDate
747 Inventories Concept (Monetary) As Of Debit ifrs-full:InventoryRecognisedAsOfAcquisitionDate
748 E&E Assets Concept (Monetary) As Of Debit cve:ExplorationAndEvaluationAssetsRecognisedAsOfAcquisitionDate
749 PP&E Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipmentRecognisedAsOfAcquisitionDate
750 Other Assets Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsRecognisedAsOfAcquisitionDate
751 Accounts Payable and Accrued Liabilities Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherPayablesRecognisedAsOfAcquisitionDate
752 Decommissioning Liabilities Concept (Monetary) As Of Credit ifrs-full:NoncurrentLiabilitiesRecognisedAsOfAcquisitionDate
753 Other Liabilities Concept (Monetary) As Of Credit cve:OtherLiabilitiesRecognisedAsOfAcquisitionDate
754 Deferred Income Taxes Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilitiesRecognisedAsOfAcquisitionDate
755 Total Identifiable Net Assets Concept (Monetary) As Of Debit ifrs-full:IdentifiableAssetsAcquiredLiabilitiesAssumed
756 100900 - Disclosure - Acquisition - Summary of Fair Value of the Consideration (Detail) Network

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757 Disclosure Of Business Combinations [Table] Table

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758 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
759 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
760 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
761 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
762 Common Shares Concept (Monetary) As Of Credit ifrs-full:EquityInterestsOfAcquirer
763 Cash Concept (Monetary) As Of Credit ifrs-full:CashTransferred
764 Fair value of consideration Concept (Monetary) As Of Credit cve:CashAndEquityInterestsOfAcquirerTransferred
765 Estimated Contingent Payment (Note 23) Concept (Monetary) As Of Credit ifrs-full:ContingentLiabilitiesRecognisedInBusinessCombination
766 Total Consideration Concept (Monetary) As Of Credit ifrs-full:AcquisitiondateFairValueOfTotalConsiderationTransferred
767 100910 - Disclosure - Acquisition - Summary of Goodwill arising from Acquisition (Detail) Network

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768 Disclosure Of Business Combinations [Table] Table

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 ifrs-full:DisclosureOfBusinessCombinationsTable
769 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
770 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
771 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
772 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
773 Total Purchase Consideration Concept (Monetary) As Of Credit ifrs-full:AcquisitiondateFairValueOfTotalConsiderationTransferred
774 Fair Value of Pre-Existing 50 Percent Ownership Interest in FCCL Concept (Monetary) As Of Credit ifrs-full:AcquisitiondateFairValueOfEquityInterestInAcquireeHeldByAcquirerImmediatelyBeforeAcquisitionDate
775 Fair Value of Identifiable Net Assets Concept (Monetary) As Of Debit ifrs-full:IdentifiableAssetsAcquiredLiabilitiesAssumed
776 Goodwill Concept (Monetary) For Period Debit ifrs-full:AdditionalRecognitionGoodwill
777 100920 - Disclosure - Acquisition - Summary of Goodwill arising from Acquisition (Parenthetical) (Detail) Network

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778 Disclosure Of Business Combinations [Table] Table

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 ifrs-full:DisclosureOfBusinessCombinationsTable
779 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
780 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
781 FCCL [Member] Member cve:FCCLPartnershipMember
782 Disclosure Of Business Combinations [Line Items] LineItems ifrs-full:DisclosureOfBusinessCombinationsLineItems
783 Percentage of voting equity interests acquired Concept (Percent) As Of ifrs-full:PercentageOfVotingEquityInterestsAcquired
784 100930 - Disclosure - Impairment Charges and Reversals - Additional Information (Detail) Network

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785 Disclosure Of Impairment Loss And Reversal Of Impairment Loss [Table] Table

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 ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossTable
786 Segments [axis] Axis ifrs-full:SegmentsAxis
787 Segments [member] Member ifrs-full:SegmentsMember
788 Deep Basin [Member] Member cve:DeepBasinSegmentMember
789 Deep Basin [Member] Member cve:DeepBasinMember
790 Oil Sands [Member] Member cve:OilSandsSegmentMember
791 Conventional [Member] Member cve:ConventionalSegmentMember
792 Corporate and Eliminations [Member] Member cve:CorporateAndEliminationsSegmentMember
793 Individual assets or cash-generating units [axis] Axis ifrs-full:IndividualAssetsOrCashgeneratingUnitsAxis
794 Entity's total for individual assets or cash-generating units [member] Member ifrs-full:EntitysTotalForIndividualAssetsOrCashgeneratingUnitsMember
795 Clearwater CGU [Member] Member cve:ClearwaterCashGeneratingUnitMember
796 Northern Alberta CGU [Member] Member cve:NorthernAlbertaCashGeneratingUnitMember
797 Suffield CGU [Member] Member cve:SuffieldCashGeneratingUnitMember
798 Borealis CGU [Member] Member cve:BorealisCashGeneratingUnitMember
799 Range [axis] Axis ifrs-full:RangeAxis
800 Ranges [member] Member ifrs-full:RangesMember
801 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
802 Top of range [Member] Member ifrs-full:TopOfRangeMember
803 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
804 Assets [member] Member ifrs-full:ClassesOfAssetsMember
805 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
806 E&E [Member] Member ifrs-full:ExplorationAndEvaluationAssetsMember
807 Disclosure Of Impairment Loss And Reversal Of Impairment Loss [Line Items] LineItems ifrs-full:DisclosureOfImpairmentLossAndReversalOfImpairmentLossLineItems
808 Goodwill impairments Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossGoodwill
809 Impairment losses Concept (Monetary) For Period Debit ifrs-full:ImpairmentLossRecognisedInProfitOrLoss
810 Impairment recoverable value Concept (Monetary) As Of Debit ifrs-full:RecoverableAmountOfAssetOrCashgeneratingUnit
811 Reversed of impairment loss Concept (Monetary) For Period Credit ifrs-full:ReversalOfImpairmentLoss
812 Description of key assumptions in determining fair value less costs of disposal Concept (Text/String) For Period ifrs-full:DescriptionOfKeyAssumptionsOnWhichManagementHasBasedDeterminationOfFairValueLessCostsOfDisposal
813 Discounted future cash flows, discount rate Concept (Percent) As Of ifrs-full:DiscountRateUsedInCurrentMeasurementOfFairValueLessCostsOfDisposal
814 Discounted future cash flows, inflation rate Concept (Percent) As Of cve:InflationRateUsedInCurrentMeasurementOfFairValueLessCostsOfDisposal
815 Impairment reversal value Concept (Monetary) For Period Credit ifrs-full:ReversalOfImpairmentLossRecognisedInProfitOrLoss
816 DD&A Impairment value recorded Concept (Monetary) For Period Debit ifrs-full:DepreciationAmortisationAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLoss
817 Percentage of reduction in expected future operating costs Concept (Percent) For Period cve:PercentageOfMainEventsAndCircumstancesThatLedToRecognitionOfImpairmentLossesAndReversalsOfImpairmentLosses
818 Exploration Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseArisingFromExplorationForAndEvaluationOfMineralResources
819 100940 - Disclosure - Impairment Charges and Reversals - Summary of Forward Prices Used to Determine Future Cash Flows (Detail) Network

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820 Disclosure Of Information For Individual Asset Or Cash Generating Unit [Table] Table

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 cve:DisclosureOfInformationForIndividualAssetOrCashGeneratingUnitTable
821 Valuation techniques used in fair value measurement [axis] Axis ifrs-full:ValuationTechniquesUsedInFairValueMeasurementAxis
822 Valuation techniques [member] Member ifrs-full:ValuationTechniquesMember
823 Commodity Price Assumptions [Member] Member cve:CommodityPriceAssumptionsMember
824 Individual assets or cash-generating units [axis] Axis ifrs-full:IndividualAssetsOrCashgeneratingUnitsAxis
825 Entity's total for individual assets or cash-generating units [member] Member ifrs-full:EntitysTotalForIndividualAssetsOrCashgeneratingUnitsMember
826 WTI [Member] Member cve:WestTexasIntermediateCrudeOilMember
827 WCS [Member] Member cve:WesternCanadianSelectCrudeOilBlendMember
828 Edmonton C5+ [Member] Member cve:EdmontonCFiveCrudeOilBlendMember
829 AECO [Member] Member cve:AECONaturalGasMember
830 Maturity [axis] Axis ifrs-full:MaturityAxis
831 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
832 2019 [Member] Member cve:TwoThousandAndNineteenMember
833 2020 [Member] Member cve:TwoThousandAndTwentyMember
834 2021 [Member] Member cve:TwoThousandAndTwentyOneMember
835 2022 [Member] Member cve:TwoThousandAndTwentyTwoMember
836 2023 [Member] Member cve:TwoThousandAndTwentyThreeMember
837 2018 [Member] Member cve:TwoThousandAndEighteenMember
838 Disclosure Of Information For Individual Asset Or Cash Generating Unit [Line Items] LineItems cve:DisclosureOfInformationForIndividualAssetOrCashGeneratingUnitLineItems
839 Average Price Concept (Decimal) As Of cve:AveragePrice
840 Average Annual Increase Thereafter Concept (Percent) As Of cve:AverageAnnualPriceIncreaseThereafter
841 100950 - Disclosure - Assets Held for Sale and Discontinued Operations - Additional Information (Detail) Network

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842 Disclosure Of Discontinued Operations [Table] Table

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843 Continuing and discontinued operations [axis] Axis ifrs-full:ContinuingAndDiscontinuedOperationsAxis
844 Aggregate continuing and discontinued operations [member] Member ifrs-full:AggregateContinuingAndDiscontinuedOperationsMember
845 Assets Held for Sale [Member] Member ifrs-full:DisposalGroupsClassifiedAsHeldForSaleMember
846 Suffield Divestiture [Member] Member cve:SuffieldDivestitureMember
847 Conventional [Member] Member cve:ConventionalSegmentMember
848 Range [axis] Axis ifrs-full:RangeAxis
849 Ranges [member] Member ifrs-full:RangesMember
850 Top of range [Member] Member ifrs-full:TopOfRangeMember
851 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
852 Measurement [axis] Axis ifrs-full:MeasurementAxis
853 Aggregated measurement [member] Member ifrs-full:AggregatedMeasurementMember
854 WTI [Member] Member cve:WestTexasIntermediateCrudeOilMember
855 Henry Hub Member cve:HenryHubMember
856 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
857 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
858 Crude oil contracts [Member] Member cve:CrudeOilContractsMember
859 Natural gas contracts [Member] Member cve:NaturalGasContractsMember
860 Disclosure Of Discontinued Operations [Line Items] LineItems cve:DisclosureOfDiscontinuedOperationsLineItems
861 Impairment of assets Concept (Monetary) For Period Debit ifrs-full:ImpairmentLoss
862 Assets Held for Sale Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale
863 Cash proceeds from sale of assets Concept (Monetary) For Period Debit ifrs-full:ProceedsFromDisposalOfNoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSaleAndDiscontinuedOperations
864 Gain (Loss) before tax on sale of assets Concept (Monetary) For Period Credit ifrs-full:GainLossRecognisedOnMeasurementToFairValueLessCostsToSellOrOnDisposalOfAssetsOrDisposalGroupsConstitutingDiscontinuedOperation
865 Purchase price adjustments Concept (Monetary) For Period Debit cve:MaximumPossibleFutureDeferredPurchasePriceAdjustment
866 Average daily crude oil price Concept (Decimal) For Period cve:AverageCrudeOilPrice
867 Average natural gas price Concept (Decimal) For Period cve:AverageNaturalGasPrice
868 Purchase price adjustments Concept (Monetary) For Period Debit cve:MaximumPossibleFutureMonthlyDeferredPurchasePriceAdjustment
869 Fair value of deferred purchase price adjustment Concept (Monetary) For Period Debit cve:FairValueOfDeferredPurchasePriceAdjustment
870 100960 - Disclosure - Assets Held for Sale and Discontinued Operations - Summary of Assets and Liabilities Held for Sale (Detail) Network

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871 Disclosure Of Assets And Liabilities Classified As Held For Sale [Table] Table

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872 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
873 Assets [member] Member ifrs-full:ClassesOfAssetsMember
874 E&E Asset [Member] Member ifrs-full:ExplorationAndEvaluationAssetsMember
875 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
876 Continuing and discontinued operations [axis] Axis ifrs-full:ContinuingAndDiscontinuedOperationsAxis
877 Aggregate continuing and discontinued operations [member] Member ifrs-full:AggregateContinuingAndDiscontinuedOperationsMember
878 Conventional [Member] Member cve:ConventionalSegmentMember
879 Deep Basin [Member] Member cve:DeepBasinMember
880 Disclosure Of Assets And Liabilities Classified As Held For Sale [Line Items] LineItems cve:DisclosureOfAssetsAndLiabilitiesClassifiedAsHeldForSaleLineItems
881 Noncurrent assets held for sale Concept (Monetary) As Of Debit ifrs-full:NoncurrentAssetsOrDisposalGroupsClassifiedAsHeldForSale
882 Decommissioning Liabilities Concept (Monetary) As Of Credit ifrs-full:LiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSale
883 100970 - Disclosure - Assets Held for Sale and Discontinued Operations - Results of Discontinued Operations (Detail) Network

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884 Implied Table Table

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885 Disclosure Of Discontinued Operations [Abstract] Abstract cve:DisclosureOfDiscontinuedOperationsAbstract
886 Revenues Abstract cve:RevenuesDiscontinuedOperationsAbstract
887 Gross Sales Concept (Monetary) For Period Credit cve:RevenueFromGrossSalesDiscontinuedOperations
888 Less: Royalties Concept (Monetary) For Period Debit cve:RoyaltyExpenseDiscontinuedOperations
889 Revenue Concept (Monetary) For Period Credit ifrs-full:RevenueDiscontinuedOperations
890 Expenses Abstract cve:ExpensesDiscontinuedOperationsAbstract
891 Transportation and Blending Concept (Monetary) For Period Debit cve:TransportationExpenseDiscontinuedOperations
892 Operating Concept (Monetary) For Period Debit cve:OperatingExpenseDiscontinuedOperations
893 Production and Mineral Taxes Concept (Monetary) For Period Debit cve:ProductionAndMineralTaxesDiscontinuedOperations
894 (Gain) Loss on Risk Management Concept (Monetary) For Period Credit cve:GainsLossesOnChangeInFairValueOfDerivativesDiscontinuedOperations
895 Operating Margin Concept (Monetary) For Period Credit cve:OperatingMarginDiscontinuedOperations
896 Depreciation, Depletion and Amortization Concept (Monetary) For Period Debit cve:DepreciationAmortisationAndImpairmentLossReversalOfImpairmentLossRecognisedInProfitOrLossDiscontinuedOperations
897 Exploration Expense Concept (Monetary) For Period Debit cve:ExpenseArisingFromExplorationForAndEvaluationOfMineralResourcesDiscontinuedOperations
898 Finance Costs Concept (Monetary) For Period Debit cve:FinanceCostsDiscontinuedOperations
899 Earnings (Loss) From Discontinued Operations Before Income Tax Concept (Monetary) For Period Credit ifrs-full:ProfitLossBeforeTaxDiscontinuedOperations
900 Current Tax Expense (Recovery) Concept (Monetary) For Period Debit cve:CurrentTaxExpenseRecoveryRelatingToProfitLossFromOrdinaryActivitiesOfDiscontinuedOperations
901 Deferred Tax Expense (Recovery) Concept (Monetary) For Period Debit cve:DeferredTaxExpenseRecoveryRelatingToProfitLossFromOrdinaryActivitiesOfDiscontinuedOperations
902 After-tax Earnings (Loss) From Discontinued Operations Concept (Monetary) For Period Credit cve:ProfitLossAfterTaxDiscontinuedOperations
903 After-tax Gain (Loss) on Discontinuance Concept (Monetary) For Period Debit cve:GainLossAfterTaxRecognisedOnMeasurementToFairValueLessCostsToSellOrOnDisposalOfAssetsOrDisposalGroupsConstitutingDiscontinuedOperation
904 Net Earnings (Loss) From Discontinued Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromDiscontinuedOperations
905 100980 - Disclosure - Assets Held for Sale and Discontinued Operations - Results of Discontinued Operations (Parenthetical) (Detail) Network

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906 Implied Table Table

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907 Disclosure Of Discontinued Operations [Abstract] Abstract cve:DisclosureOfDiscontinuedOperationsAbstract
908 Net Deferred Tax Expense Concept (Monetary) For Period Debit ifrs-full:TaxExpenseRelatingToGainLossOnDiscontinuance
909 100990 - Disclosure - Assets Held for Sale and Discontinued Operations - Summary of Cash Flows from Discontinued Operations (Detail) Network

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910 Implied Table Table

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911 Cash Flows From Discontinued Operations [Abstract] Abstract cve:CashFlowsFromDiscontinuedOperationsAbstract
912 Cash From (Used in) Operating Activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInOperatingActivitiesDiscontinuedOperations
913 Cash From (Used in) Investing Activities Concept (Monetary) For Period Debit ifrs-full:CashFlowsFromUsedInInvestingActivitiesDiscontinuedOperations
914 Net Cash Flow Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInCashAndCashEquivalentsDiscontinuedOperations
915 101000 - Disclosure - Income Taxes - Provision for Income Taxes (Detail) Network

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916 Disclosure Of Components Of Tax Expense Income [Table] Table

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 cve:DisclosureOfComponentsOfTaxExpenseIncomeTable
917 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
918 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
919 Canada [Member] Member country:CA
920 United States [member] Member country:US
921 Major Components Of Tax Expense Income [Line Items] LineItems cve:MajorComponentsOfTaxExpenseIncomeLineItems
922 Current Tax Expense (Recovery) Concept (Monetary) For Period Debit cve:CurrentIncomeTaxExpenseContinuingOperations
923 Deferred Tax Expense (Recovery) Concept (Monetary) For Period Debit cve:DeferredIncomeTaxExpenseContinuingOperations
924 Tax Expense (Recovery) From Continuing Operations Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
925 101010 - Disclosure - Income Taxes - Additional Information (Detail) Network

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926 Disclosure Of Income Taxes [Table] Table

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 cve:DisclosureOfIncomeTaxesTable
927 Temporary difference, unused tax losses and unused tax credits [axis] Axis ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis
928 Temporary difference, unused tax losses and unused tax credits [member] Member ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember
929 Reduction of U.S. Federal Corporate Income Tax Rate Member ifrs-full:ChangesInTaxRatesOrTaxLawsEnactedOrAnnouncedMember
930 Segment consolidation items [axis] Axis ifrs-full:SegmentConsolidationItemsAxis
931 Entity's total for segment consolidation items [member] Member ifrs-full:EntitysTotalForSegmentConsolidationItemsMember
932 Canadian Federal Non Capital Losses [Member] Member cve:CanadianFederalNonCapitalLossesMember
933 US Federal Net Operating Losses [Member] Member cve:UsFederalNetOperatingLossesMember
934 Canadian Net Capital Losses [Member] Member cve:CanadianNetCapitalLossesMember
935 Disclosure of income taxes [line items] LineItems cve:DisclosureOfIncomeTaxesLineItems
936 Deferred tax (expense) recovery Concept (Monetary) For Period Debit cve:DeferredTaxImpactOfAdjustmentToUSTaxBasis
937 Income tax rate Concept (Percent) For Period cve:USFederalCorporateIncomeTaxRateHistorical
938 Income tax rate, current Concept (Percent) For Period cve:USFederalCorporateIncomeTaxRateCurrent
939 Deferred tax liability has been recognized Concept (Monetary) As Of ifrs-full:TemporaryDifferencesAssociatedWithInvestmentsInSubsidiariesBranchesAndAssociatesAndInterestsInJointVentures
940 Amounts of tax pools available, including tax losses Concept (Monetary) As Of Credit cve:TaxPoolsAvailable
941 Unrecognized as a deferred income tax asset Concept (Monetary) As Of ifrs-full:UnusedTaxLossesForWhichNoDeferredTaxAssetRecognised
942 Net capital losses associated with unrealized foreign exchange losses Concept (Monetary) For Period Credit cve:UnrecognizedNetCapitalLosses
943 101020 - Disclosure - Income Taxes - Reconciliation of Income Taxes Calculated at Statutory Rate (Detail) Network

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944 Implied Table Table

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945 Reconciliation Of Average Effective Tax Rate And Applicable Tax Rate [Abstract] Abstract ifrs-full:ReconciliationOfAverageEffectiveTaxRateAndApplicableTaxRateAbstract
946 Earnings (Loss) From Continuing Operations Before Income Tax Concept (Monetary) For Period Credit ifrs-full:AccountingProfit
947 Canadian Statutory Rate Concept (Percent) For Period ifrs-full:ApplicableTaxRate
948 Expected Income Tax Expense (Recovery) From Continuing Operations Concept (Monetary) For Period Debit ifrs-full:TaxExpenseIncomeAtApplicableTaxRate
949 Effect of Taxes Resulting From: Abstract cve:SourceOfOriginOfTaxRateDifferentialAbstract
950 Foreign Tax Rate Differential Concept (Monetary) For Period Debit ifrs-full:TaxEffectOfForeignTaxRates
951 Non-Taxable Capital (Gains) Losses Concept (Monetary) For Period Credit ifrs-full:TaxEffectOfRevenuesExemptFromTaxation2011
952 Non-Recognition of Capital (Gains) Losses Concept (Monetary) For Period Debit cve:TaxEffectOfNonRecognitionOfCapitalGainsLosses
953 Adjustments Arising From Prior Year Tax Filings Concept (Monetary) For Period Debit cve:AdjustmentsForTaxOfPriorPeriods
954 Recognition of Previously Unrecognized Capital Losses Concept (Monetary) For Period Debit ifrs-full:TaxEffectOfTaxLosses
955 Recognition of U.S. Tax Basis Concept (Monetary) For Period Debit cve:DeferredTaxImpactOfAdjustmentToUSTaxBasis
956 Change in Statutory Rate Concept (Monetary) For Period Debit ifrs-full:TaxEffectFromChangeInTaxRate
957 Non-Deductible Expenses Concept (Monetary) For Period Debit ifrs-full:TaxEffectOfExpenseNotDeductibleInDeterminingTaxableProfitTaxLoss
958 Other Concept (Monetary) For Period Debit ifrs-full:OtherTaxEffectsForReconciliationBetweenAccountingProfitAndTaxExpenseIncome
959 Tax Expense (Recovery) From Continuing Operations Concept (Monetary) For Period Debit ifrs-full:IncomeTaxExpenseContinuingOperations
960 Effective Tax Rate Concept (Percent) For Period ifrs-full:AverageEffectiveTaxRate
961 101030 - Disclosure - Income Taxes - Deferred Income Tax Liabilities and Deferred Income Tax Assets (Detail) Network

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962 Disclosure Of Income Taxes [Table] Table

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963 Maturity [axis] Axis ifrs-full:MaturityAxis
964 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
965 Less Than 1 Year [Member] Member ifrs-full:NotLaterThanOneYearMember
966 1 Year [Member] Member ifrs-full:LaterThanOneYearMember
967 Disclosure of income taxes [line items] LineItems cve:DisclosureOfIncomeTaxesLineItems
968 Deferred Income Tax Liabilities Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilities
969 Deferred Income Tax Assets Concept (Monetary) As Of Debit ifrs-full:DeferredTaxAssets
970 Net Deferred Income Tax Liability Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
971 101040 - Disclosure - Income Taxes - Schedule of Movement in Deferred Income Tax Liabilities and Assets (Detail) Network

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972 Reconciliation Of Changes In Deferred Tax Liability Asset [Table] Table

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973 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
974 Assets [member] Member ifrs-full:ClassesOfAssetsMember
975 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
976 Timing of Partnership Items [Member] Member cve:TimingOfPartnershipItemsMember
977 Risk Management [Member] Member cve:DerivativeFinancialInstrumentsMember
978 Other [Member] Member ifrs-full:OtherAssetsMember
979 Assets and liabilities [axis] Axis ifrs-full:AssetsAndLiabilitiesAxis
980 Assets and liabilities [member] Member ifrs-full:AssetsAndLiabilitiesMember
981 Deferred Income Tax Liabilities [Member] Member cve:DeferredIncomeTaxLiabilitiesMember
982 Deferred Income Tax Assets [Member] Member cve:DeferredIncomeTaxAssetsMember
983 Net Deferred Income Tax Liabilities [Member] Member cve:NetDeferredIncomeTaxLiabilitiesMember
984 Temporary difference, unused tax losses and unused tax credits [axis] Axis ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsAxis
985 Temporary difference, unused tax losses and unused tax credits [member] Member ifrs-full:TemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsMember
986 Unused Tax Losses [Member] Member ifrs-full:UnusedTaxLossesMember
987 Reconciliation Of Changes In Deferred Tax Liability Asset [Line Items] LineItems cve:ReconciliationOfChangesInDeferredTaxLiabilityAssetLineItems
988 Deferred Income Tax Liabilities, Beginning Balance Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilities
989 Charged (Credited) to Earnings Concept (Monetary) For Period ifrs-full:DeferredTaxExpenseIncomeRecognisedInProfitOrLoss
990 Charged (Credited) to Purchase Price Allocation Concept (Monetary) For Period cve:DeferredTaxExpenseIncomeRelatingToPurchasePriceAllocation
991 Charged (Credited) to OCI Concept (Monetary) For Period cve:DeferredTaxExpenseIncomeRecognisedInOtherComprehensiveIncome
992 Deferred Income Tax Liabilities, Ending Balance Concept (Monetary) As Of Credit ifrs-full:DeferredTaxLiabilities
993 Deferred Income Tax Assets, Beginning Balance Concept (Monetary) As Of Debit ifrs-full:DeferredTaxAssets
994 Charged (Credited) to Share Capital Concept (Monetary) For Period cve:DeferredTaxExpenseIncomeRecognisedInShareCapital
995 Deferred Income Tax Assets, Ending Balance Concept (Monetary) As Of Debit ifrs-full:DeferredTaxAssets
996 Net Deferred Income Tax Liabilities, Beginning Balance Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
997 Net Deferred Income Tax Liabilities, Ending Balance Concept (Monetary) As Of Credit ifrs-full:NetDeferredTaxLiabilities
998 101050 - Disclosure - Income Taxes - Schedule of Amounts of Tax Pools Available, Including Tax Losses (Detail) Network

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999 Disclosure Of Temporary Difference Unused Tax Losses And Unused Tax Credits [Table] Table

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1000 Geographical areas [axis] Axis ifrs-full:GeographicalAreasAxis
1001 Geographical areas [member] Member ifrs-full:GeographicalAreasMember
1002 Canada [Member] Member country:CA
1003 United States [member] Member country:US
1004 Disclosure of temporary difference, unused tax losses and unused tax credits [Line Items] LineItems ifrs-full:DisclosureOfTemporaryDifferenceUnusedTaxLossesAndUnusedTaxCreditsLineItems
1005 Amounts of tax pools available, including tax losses Concept (Monetary) As Of Credit cve:TaxPoolsAvailable
1006 101060 - Disclosure - Per Share Amounts - Schedule Representing Per Share Amounts (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosurePerShareAmountsScheduleRepresentingPerShareAmountsDetail
1007 Implied Table Table

*

*

 implied:Table
1008 Earnings Per Share [Abstract] Abstract ifrs-full:EarningsPerShareAbstract
1009 Earnings (Loss) From: Abstract ifrs-full:ProfitLossAbstract
1010 Continuing Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromContinuingOperations
1011 Discontinued Operations Concept (Monetary) For Period Credit ifrs-full:ProfitLossFromDiscontinuedOperations
1012 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
1013 Basic - Weighted Average Number of Shares (millions) Concept (Shares) For Period ifrs-full:WeightedAverageShares
1014 Dilutive Effect of Cenovus NSRs Concept (Shares) For Period ifrs-full:DilutiveEffectOfShareOptionsOnNumberOfOrdinaryShares
1015 Diluted - Weighted Average Number of Shares Concept (Shares) For Period ifrs-full:AdjustedWeightedAverageShares
1016 Basic and Diluted Earnings (Loss) Per Share ($) Abstract ifrs-full:BasicAndDilutedEarningsPerShareAbstract
1017 Continuing Operations Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShareFromContinuingOperations
1018 Discontinued Operations Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShareFromDiscontinuedOperations
1019 Net Earnings (Loss) Per Share Concept (Share) For Period ifrs-full:BasicAndDilutedEarningsLossPerShare
1020 101070 - Disclosure - Per Share Amounts - Additional Information (Detail) Network

*

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 http://www.cenovus.com/20181231/taxonomy/role/DisclosurePerShareAmountsAdditionalInformationDetail
1021 Earnings Per Share [Table] Table

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*

 ifrs-full:EarningsPerShareTable
1022 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1023 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1024 NSRs [Member] Member cve:NetSettlementRightsMember
1025 TSARs [Member] Member cve:TandemStockAppreciationRightsMember
1026 Earnings Per Share [Line Items] LineItems ifrs-full:EarningsPerShareLineItems
1027 Options excluded from diluted weighted average number of shares Concept (Shares) For Period cve:EquityInstrumentsWithPotentialFutureDilutiveEffectNotIncludedInCalculationOfDilutedEarningsPerShare
1028 Dividends paid on common shares Concept (Monetary) For Period Debit ifrs-full:DividendsPaid
1029 Dividend paid per share Concept (Share) For Period ifrs-full:DividendsPaidOrdinarySharesPerShare
1030 Dividend declared but not paid Concept (Share) For Period ifrs-full:DividendsProposedOrDeclaredBeforeFinancialStatementsAuthorisedForIssueButNotRecognisedAsDistributionToOwnersPerShare
1031 101080 - Disclosure - Cash and Cash Equivalents - Schedule Representing Cash and Cash Equivalents (Detail) Network

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1032 Implied Table Table

*

*

 implied:Table
1033 Cash And Cash Equivalents [Abstract] Abstract ifrs-full:CashAndCashEquivalentsAbstract
1034 Cash Concept (Monetary) As Of Debit ifrs-full:BalancesWithBanks
1035 Short-Term Investments Concept (Monetary) As Of Debit ifrs-full:ShorttermInvestmentsClassifiedAsCashEquivalents
1036 Total Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
1037 101090 - Disclosure - Accounts Receivables and Accrued Revenues - Schedule of accounts receivables and accrued revenues (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureAccountsReceivablesAndAccruedRevenuesScheduleOfAccountsReceivablesAndAccruedRevenuesDetail
1038 Implied Table Table

*

*

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1039 Trade And Other Current Receivables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentReceivablesAbstract
1040 Accruals Concept (Monetary) As Of Debit ifrs-full:CurrentAccruedIncome
1041 Prepaids and Deposits Concept (Monetary) As Of Debit cve:CurrentPrepaidsAndDeposits
1042 Partner Advances Concept (Monetary) As Of Debit cve:CurrentAdvancesToPartner
1043 Trade Concept (Monetary) As Of Debit ifrs-full:CurrentTradeReceivables
1044 Joint Operations Receivables Concept (Monetary) As Of Debit cve:CurrentJointOperationsReceivables
1045 Other Concept (Monetary) As Of Debit ifrs-full:OtherCurrentReceivables
1046 Accounts Receivable and Accrued Revenues Concept (Monetary) As Of Debit ifrs-full:TradeAndOtherCurrentReceivables
1047 101100 - Disclosure - Inventories - Schedule of Inventories (Detail) Network

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*

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1048 Disclosure Of Inventories [Table] Table

*

*

 cve:DisclosureOfInventoriesTable
1049 Segments [axis] Axis ifrs-full:SegmentsAxis
1050 Segments [member] Member ifrs-full:SegmentsMember
1051 Refining and Marketing [Member] Member cve:RefiningAndMarketingSegmentMember
1052 Oil Sands [Member] Member cve:OilSandsSegmentMember
1053 Deep Basin [Member] Member cve:DeepBasinSegmentMember
1054 Conventional [Member] Member cve:ConventionalSegmentMember
1055 Disclosure of inventories [line items] LineItems cve:DisclosureOfInventoriesLineItems
1056 Refining and Marketing Concept (Monetary) As Of Debit ifrs-full:WorkInProgress
1057 Crude Oil Concept (Monetary) As Of Debit ifrs-full:CurrentCrudeOil
1058 Parts and Supplies Concept (Monetary) As Of Debit ifrs-full:OtherInventories
1059 Inventories Concept (Monetary) As Of Debit ifrs-full:Inventories
1060 101110 - Disclosure - Inventories - Additional Information (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureInventoriesAdditionalInformationDetail
1061 Disclosure Of Inventories [Table] Table

*

*

 cve:DisclosureOfInventoriesTable
1062 Segments [axis] Axis ifrs-full:SegmentsAxis
1063 Segments [member] Member ifrs-full:SegmentsMember
1064 Refined Product [Member] Member cve:RefinedProductMember
1065 Disclosure of inventories [line items] LineItems cve:DisclosureOfInventoriesLineItems
1066 Cost of inventories recognized as expense during period Concept (Monetary) For Period Debit ifrs-full:CostOfInventoriesRecognisedAsExpenseDuringPeriod
1067 Inventory write-down Concept (Monetary) For Period ifrs-full:InventoryWritedown2011
1068 101120 - Disclosure - Exploration and Evaluation Assets - Summary of Exploration and Valuation Assets (Detail) Network

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1069 Disclosure Of Exploration And Evaluation Assets [Table] Table

*

*

 cve:DisclosureOfExplorationAndEvaluationAssetsTable
1070 Classes of assets [axis] Axis ifrs-full:ClassesOfAssetsAxis
1071 Assets [member] Member ifrs-full:ClassesOfAssetsMember
1072 E&E [Member] Member ifrs-full:ExplorationAndEvaluationAssetsMember
1073 Disclosure Of Exploration And Evaluation Assets [Line Items] LineItems cve:DisclosureOfExplorationAndEvaluationAssetsLineItems
1074 Beginning Balance Concept (Monetary) As Of Debit ifrs-full:IntangibleExplorationAndEvaluationAssets
1075 Additions Concept (Monetary) For Period Debit cve:AdditionsOfExplorationAndEvaluationAssets
1076 Acquisition Concept (Monetary) For Period Debit cve:IncreaseFromAcquisitionOfExplorationAndEvaluationAssets
1077 Transfers to/from Assets Held for Sale Concept (Monetary) For Period Credit cve:DecreaseThroughTransferToAssetsIncludedInDisposalGroupsClassifiedAsHeldForSale
1078 Transfers from Assets Held for Sale (Note 11) Concept (Monetary) For Period Debit cve:DecreaseThroughTransferFromAssetsIncludedInDisposalGroupsClassifiedAsHeldForSale
1079 Transfers to PP&E Concept (Monetary) For Period Debit cve:DecreaseThroughTransfersPropertyPlantAndEquipment
1080 Exploration Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseArisingFromExplorationForAndEvaluationOfMineralResources
1081 Change in Decommissioning Liabilities Concept (Monetary) For Period Credit cve:IncreaseDecreaseInExplorationAndEvaluationAssetsFromChangesInProvisionForDecommissioningRestorationAndRehabilitationCosts
1082 Exchange Rate Movements and Other Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughForeignExchangeAndOtherMovementsFinancialAssets
1083 Other Concept (Monetary) For Period Debit cve:OtherIntangibleExplorationAndEvaluationAssets
1084 Divestitures Concept (Monetary) For Period Credit cve:Divestitures
1085 Ending Balance Concept (Monetary) As Of Debit ifrs-full:IntangibleExplorationAndEvaluationAssets
1086 101130 - Disclosure - Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment (Detail) Network

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*

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1087 Disclosure Of Property Plant And Equipment [Table] Table

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*

 ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
1088 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
1089 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
1090 Development & Production Upstream Assets [Member] Member cve:DevelopmentAndProductionMember
1091 Other Upstream Assets [Member] Member cve:OtherUpstreamAssetsMember
1092 Refining Equipment [Member] Member cve:RefiningEquipmentsMember
1093 Other [Member] Member ifrs-full:OtherPropertyPlantAndEquipmentMember
1094 Carrying amount, accumulated depreciation, amortisation and impairment and gross carrying amount [axis] Axis ifrs-full:CarryingAmountAccumulatedDepreciationAmortisationAndImpairmentAndGrossCarryingAmountAxis
1095 Carrying amount [member] Member ifrs-full:CarryingAmountMember
1096 Cost [Member] Member ifrs-full:GrossCarryingAmountMember
1097 Accumulated depreciation and amortisation [Member] Member ifrs-full:AccumulatedDepreciationAndAmortisationMember
1098 Disclosure Of Property Plant And Equipment [Line Items] LineItems ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
1099 Beginning Balance Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
1100 Additions Concept (Monetary) For Period Debit ifrs-full:AdditionsOtherThanThroughBusinessCombinationsPropertyPlantAndEquipment
1101 Acquisition Concept (Monetary) For Period Debit ifrs-full:AcquisitionsThroughBusinessCombinationsPropertyPlantAndEquipment
1102 Transfers From E&E Assets Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughTransfersPropertyPlantAndEquipment
1103 Transfers to/from Assets Held for Sale Concept (Monetary) For Period Credit cve:DecreaseThroughTransferToAssetsIncludedInDisposalGroupsClassifiedAsHeldForSale
1104 Change in Decommissioning Liabilities Concept (Monetary) For Period Debit cve:IncreaseDecreaseThroughDecommissioningLiabilitiesPropertyPlantAndEquipment
1105 Exchange Rate Movements and Other Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseThroughOtherChangesPropertyPlantAndEquipment
1106 Divestitures Concept (Monetary) For Period Credit ifrs-full:DisposalsPropertyPlantAndEquipment
1107 Ending Balance Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipment
1108 DD&A Concept (Monetary) For Period ifrs-full:DepreciationPropertyPlantAndEquipment
1109 Impairment Losses Concept (Monetary) For Period ifrs-full:ImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment
1110 Impairment Reversals (Note 10) Concept (Monetary) For Period ifrs-full:ReversalOfImpairmentLossRecognisedInProfitOrLossPropertyPlantAndEquipment
1111 101140 - Disclosure - Property, Plant and Equipment, Net - Summary of Property, Plant and Equipment (Parenthetical) (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosurePropertyPlantAndEquipmentNetSummaryOfPropertyPlantAndEquipmentParentheticalDetail
1112 Disclosure Of Property Plant And Equipment [Table] Table

*

*

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1113 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
1114 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
1115 FCCL [Member] Member cve:FCCLPartnershipMember
1116 Disclosure Of Property Plant And Equipment [Line Items] LineItems ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
1117 Carrying value of the pre-existing interest in FCCL Concept (Monetary) As Of Credit cve:CarryingValueOfPreExistingInterestPPAndE
1118 101150 - Disclosure - Property, Plant and Equipment, Net - Summary of PP&E Under Construction and Not Subject to DD&A (Detail) Network

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1119 Disclosure Of Property Plant And Equipment [Table] Table

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*

 ifrs-full:DisclosureOfPropertyPlantAndEquipmentTable
1120 Classes of property, plant and equipment [axis] Axis ifrs-full:ClassesOfPropertyPlantAndEquipmentAxis
1121 Property, plant and equipment [member] Member ifrs-full:PropertyPlantAndEquipmentMember
1122 Development & Production Upstream Assets [Member] Member cve:DevelopmentAndProductionMember
1123 Refining Equipment [Member] Member cve:RefiningEquipmentsMember
1124 Disclosure Of Property Plant And Equipment [Line Items] LineItems ifrs-full:DisclosureOfPropertyPlantAndEquipmentLineItems
1125 Property Plant and Equipment Temporarily Idle Concept (Monetary) As Of Debit ifrs-full:PropertyPlantAndEquipmentExpendituresRecognisedForConstructions
1126 101160 - Disclosure - Other Assets - Schedule of Other Assets (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureOtherAssetsScheduleOfOtherAssetsDetail
1127 Implied Table Table

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*

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1128 Other Noncurrent Assets [Abstract] Abstract cve:OtherNoncurrentAssetsAbstract
1129 Equity Investments Concept (Monetary) As Of Debit cve:InvestmentsInPrivateEquityCompanies
1130 Long-Term Receivables Concept (Monetary) As Of Debit ifrs-full:NoncurrentReceivables
1131 Prepaids Concept (Monetary) As Of Debit cve:NoncurrentPrepaidExpenses
1132 Other Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentNonfinancialAssets
1133 Other assets Concept (Monetary) As Of Debit ifrs-full:OtherNoncurrentAssets
1134 101170 - Disclosure - Goodwill - Summary of Carrying Value of Goodwill (Detail) Network

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*

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1135 Implied Table Table

*

*

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1136 Disclosure Of Reconciliation Of Changes In Goodwill [Abstract] Abstract ifrs-full:DisclosureOfReconciliationOfChangesInGoodwillAbstract
1137 Carrying Value, Beginning of Year Concept (Monetary) As Of Debit ifrs-full:Goodwill
1138 Goodwill Recognized on Acquisition (Note 9) Concept (Monetary) For Period Debit ifrs-full:AdditionalRecognitionGoodwill
1139 Carrying Value, End of Year Concept (Monetary) As Of Debit ifrs-full:Goodwill
1140 101180 - Disclosure - Goodwill - Additional Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureGoodwillAdditionalInformationDetail
1141 Disclosure Of Information For Individual Asset Or Cashgenerating Unit With Significant Amount Of Goodwill Or Intangible Assets With Indefinite Useful Lives [Table] Table

*

*

 ifrs-full:DisclosureOfInformationForIndividualAssetOrCashgeneratingUnitWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesTable
1142 Individual assets or cash-generating units [axis] Axis ifrs-full:IndividualAssetsOrCashgeneratingUnitsAxis
1143 Entity's total for individual assets or cash-generating units [member] Member ifrs-full:EntitysTotalForIndividualAssetsOrCashgeneratingUnitsMember
1144 Primrose (Foster Creek) [Member] Member cve:PrimroseFosterCreekMember
1145 Christina Lake [Member] Member cve:ChristinaLakeMember
1146 Disclosure Of Information For Individual Asset Or Cashgenerating Unit With Significant Amount Of Goodwill Or Intangible Assets With Indefinite Useful Lives [Line Items] LineItems ifrs-full:DisclosureOfInformationForIndividualAssetOrCashgeneratingUnitWithSignificantAmountOfGoodwillOrIntangibleAssetsWithIndefiniteUsefulLivesLineItems
1147 Goodwill Concept (Monetary) As Of Debit ifrs-full:Goodwill
1148 101190 - Disclosure - Accounts Payable and Accrued Liabilities - Schedule of Accounts Payable and Accrued Liabilities (Detail) Network

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1149 Implied Table Table

*

*

 implied:Table
1150 Trade And Other Current Payables [Abstract] Abstract ifrs-full:TradeAndOtherCurrentPayablesAbstract
1151 Accruals Concept (Monetary) As Of Credit ifrs-full:AccrualsClassifiedAsCurrent
1152 Trade Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherCurrentPayablesToTradeSuppliers
1153 Interest Concept (Monetary) As Of Credit ifrs-full:CurrentInterestPayable
1154 Partner Advances Concept (Monetary) As Of Credit cve:CurrentAdvancesFromPartner
1155 Employee Long-Term Incentives Concept (Monetary) As Of Credit ifrs-full:LiabilitiesFromSharebasedPaymentTransactions2011
1156 Joint Operations Payable Concept (Monetary) As Of Credit cve:JointOperationsPayablesCurrent
1157 Other Concept (Monetary) As Of Credit ifrs-full:OtherCurrentPayables
1158 Accounts payable and accrued liabilities Concept (Monetary) As Of Credit ifrs-full:TradeAndOtherCurrentPayables
1159 101200 - Disclosure - Long-term Debt and Capital Structure - Schedule of Long Term Debt (Detail) Network

*

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1160 Disclosure Of Detailed Information About Borrowings [Table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1161 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1162 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1163 Revolving Term Debt [Member] Member cve:RevolvingTermDebtMember
1164 U.S. Dollar Denominated Unsecured Notes [Member] Member cve:USDollarDenominatedUnsecuredNotesMember
1165 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1166 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1167 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1168 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1169 Total Debt Principal, (CAD equivalent) Concept (Monetary) As Of Credit ifrs-full:NotesAndDebenturesIssued
1170 Debt Discounts and Transaction Costs Concept (Monetary) As Of Debit cve:DebtDiscountsAndTransactionCosts
1171 Long-term debt Concept (Monetary) As Of Credit ifrs-full:Borrowings
1172 Current Portion of Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:CurrentPortionOfLongtermBorrowings
1173 Long-Term Portion Concept (Monetary) As Of Credit ifrs-full:LongtermBorrowings
1174 101210 - Disclosure - Long-term Debt and Capital Structure - Additional Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureLongTermDebtAndCapitalStructureAdditionalInformationDetail
1175 Disclosure Of Detailed Information About Borrowings [Table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1176 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1177 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1178 Revolving Term Debt [Member] Member cve:RevolvingTermDebtMember
1179 5.70 % Due October 15, 2019 [Member] Member cve:FivePointSevenZeroPercentageDueOctoberFifteenTwoThousandNineteenMember
1180 4.25% Due April 15, 2027 [Member] Member cve:FourPointTwoFivePercentageDueAprilFifteenTwoThousandTwentySevenMember
1181 5.25% Due June 15, 2037 [Member] Member cve:FivePointTwoFivePercentageDueJuneFifteenTwoThousandThirtySevenMember
1182 5.40% Due June 15, 2047 [Member] Member cve:FivePointFourZeroPercentageDueJuneFifteenTwoThousandFortySevenMember
1183 Committed Asset Sale Bridge Credit Facility [Member] Member cve:CommittedAssetSaleBridgeCreditFacilityMember
1184 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1185 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1186 Tranche One [Member] Member cve:TrancheOneMember
1187 Tranche Two [Member] Member cve:TrancheTwoMember
1188 Credit Facility [member] Member cve:CreditFacilityMember
1189 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1190 Base Shelf Prospectus [Member] Member cve:BaseShelfProspectusMember
1191 Non-adjusting events after reporting period [axis] Axis ifrs-full:NonadjustingEventsAfterReportingPeriodAxis
1192 Non-adjusting events after reporting period [member] Member ifrs-full:NonadjustingEventsMember
1193 Events After Reporting Period [Member] Member cve:EventsAfterReportingPeriodMember
1194 Range [axis] Axis ifrs-full:RangeAxis
1195 Ranges [member] Member ifrs-full:RangesMember
1196 Top of range [Member] Member ifrs-full:TopOfRangeMember
1197 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1198 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1199 Weighted average interest rate Concept (Percent) As Of cve:WeightedAverageInterestRate
1200 Maturity date Concept (Text/String) For Period cve:MaturityDate
1201 Committed credit facility capacity Concept (Monetary) As Of Credit cve:CommittedCreditFacilityCapacity
1202 Total Debt Principal, (CAD equivalent) Concept (Monetary) As Of Credit ifrs-full:NotesAndDebenturesIssued
1203 Senior unsecured notes issued Concept (Monetary) As Of ifrs-full:NotionalAmount
1204 Redemption of debt Concept (Monetary) For Period Debit cve:RedeemptionOfDebt
1205 Redemption premium Concept (Monetary) For Period Debit cve:DebtInstrumentRedemptionPremium
1206 Associated unamortized discount and debt issue cost Concept (Monetary) For Period Debit cve:AssociatedUnamortizedDiscountAndDebtIssueCost
1207 Payment to repurchase unsecured notes Concept (Monetary) For Period Debit cve:PaymentToRepurchaseUnsecuredNotes
1208 Unsecured notes principal Concept (Monetary) As Of cve:UnsecuredNotesPrincipal
1209 Gain on repurchase recorded in finance cost Concept (Monetary) For Period Credit cve:GainOnRepurchaseRecordedInFinanceCost
1210 Payment to repurchase unsecured notes Concept (Monetary) For Period Debit cve:RepurchaseUnsecuredNotes
1211 Cash payment to repurchase unsecured notes Concept (Monetary) For Period Debit cve:CashPaymentToRepurchaseUnsecuredNotes
1212 Borrowings interest rate Concept (Percent) As Of ifrs-full:BorrowingsInterestRate
1213 Authorized capacity under base shelf prospectus Concept (Monetary) As Of cve:BaseShelfProspectusCapacity
1214 Borrowings Concept (Monetary) As Of Credit ifrs-full:Borrowings
1215 Target Net Debt to Adjusted EBITDA Ratio Concept (Percent) For Period cve:TargetDebtToAdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortizationRatio
1216 101220 - Disclosure - Long-term Debt and Capital Structure - Summary of Unsecured Notes (Detail) Network

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1217 Disclosure Of Detailed Information About Borrowings [Table] Table

*

*

 ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsTable
1218 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1219 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1220 5.70 % Due October 15, 2019 [Member] Member cve:FivePointSevenZeroPercentageDueOctoberFifteenTwoThousandNineteenMember
1221 3.00% Due August 15, 2022 [Member] Member cve:ThreePointZeroZeroPercentageDueAugustFifteenTwoThousandTwentyTwoMember
1222 3.80% Due September 15, 2023 [Member] Member cve:ThreePointEightZeroPercentageDueSeptemberFifteenTwoThousandTwentyThreeMember
1223 4.25% Due April 15, 2027 [Member] Member cve:FourPointTwoFivePercentageDueAprilFifteenTwoThousandTwentySevenMember
1224 5.25% Due June 15, 2037 [Member] Member cve:FivePointTwoFivePercentageDueJuneFifteenTwoThousandThirtySevenMember
1225 6.75% Due November 15, 2039 [Member] Member cve:SixPointSevenFivePercentageDueNovemberFifteenTwoThousandThirtyNineMember
1226 4.45% Due September 15, 2042 [Member] Member cve:FourPointFourFivePercentageDueSeptemberFifteenTwoThousandFortyTwoMember
1227 5.20% Due September 15, 2043 [Member] Member cve:FivePointTwoZeroPercentageDueSeptemberFifteenTwoThousandFortyThreeMember
1228 5.40% Due June 15, 2047 [Member] Member cve:FivePointFourZeroPercentageDueJuneFifteenTwoThousandFortySevenMember
1229 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1230 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1231 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1232 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1233 Total Debt Principal Concept (Monetary) As Of ifrs-full:NotionalAmount
1234 Total Debt Principal, (CAD equivalent) Concept (Monetary) As Of Credit ifrs-full:NotesAndDebenturesIssued
1235 101230 - Disclosure - Long-term Debt and Capital Structure - Schedule of Mandatory Debt Payments (Detail) Network

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1236 Disclosure Of Detailed Information About Borrowings [Table] Table

*

*

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1237 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1238 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1239 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1240 Maturity [axis] Axis ifrs-full:MaturityAxis
1241 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1242 Less Than 1 Year [Member] Member ifrs-full:NotLaterThanOneYearMember
1243 Later than one year and not later than two years [Member] Member ifrs-full:LaterThanOneYearAndNotLaterThanTwoYearsMember
1244 Later than two years and not later than three years [Member] Member ifrs-full:LaterThanTwoYearsAndNotLaterThanThreeYearsMember
1245 Later than three years and not later than four years [Member] Member ifrs-full:LaterThanThreeYearsAndNotLaterThanFourYearsMember
1246 Later than four years and not later than five years [Member] Member ifrs-full:LaterThanFourYearsAndNotLaterThanFiveYearsMember
1247 5 Years [Member] Member ifrs-full:LaterThanFiveYearsMember
1248 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1249 Total Debt Principal Concept (Monetary) As Of ifrs-full:NotionalAmount
1250 Total Debt Principal, (CAD equivalent) Concept (Monetary) As Of Credit ifrs-full:NotesAndDebenturesIssued
1251 101240 - Disclosure - Long-term Debt and Capital Structure - Summary of Net Debt to Adjusted EBITDA (Detail) Network

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1252 Implied Table Table

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*

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1253 Disclosure Of Objectives Policies And Processes For Managing Capital [Abstract] Abstract ifrs-full:DisclosureOfObjectivesPoliciesAndProcessesForManagingCapitalAbstract
1254 Current Portion of Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:CurrentPortionOfLongtermBorrowings
1255 Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:LongtermBorrowings
1256 Less: Cash and Cash Equivalents Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
1257 Net Debt Concept (Monetary) As Of Credit ifrs-full:NetDebt
1258 Net Earnings (Loss) Concept (Monetary) For Period Credit ifrs-full:ProfitLoss
1259 Add (Deduct): Abstract cve:AdjustmentsToEarningsForAdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortizationAbstract
1260 Finance Costs Concept (Monetary) For Period Debit cve:FinanceCostsIncludingDiscontinuedOperations
1261 Interest Income Concept (Monetary) For Period Credit ifrs-full:FinanceIncome
1262 Income Tax Expense (Recovery) Concept (Monetary) For Period Debit cve:TaxExpenseIncome
1263 DD&A Concept (Monetary) For Period Debit cve:DepreciationAmortizationAndImpairmentLossReversalForContinuingAndDiscontinuingOperations
1264 E&E Write-Down Concept (Monetary) For Period Debit cve:ExpenseArisingFromExplorationAndEvaluationForContinuingAndDiscontinuedOperations
1265 Unrealized (Gain) Loss on Risk Management Concept (Monetary) For Period Credit cve:UnrealizedGainsLossesOnChangeInFairValueOfDerivatives
1266 Foreign Exchange (Gain) Loss, Net Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
1267 Revaluation (Gain) Concept (Monetary) For Period Credit ifrs-full:GainLossRecognisedAsResultOfRemeasuringToFairValueEquityInterestInAcquireeHeldByAcquirerBeforeBusinessCombination
1268 Re-measurement of Contingent Payment Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseInContingentLiabilitiesRecognisedInBusinessCombination
1269 (Gain) Loss on Discontinuance Concept (Monetary) For Period Credit cve:GainLossOnDiscontinuance
1270 (Gain) Loss on Divestitures of Assets Concept (Monetary) For Period Credit ifrs-full:GainsOnDisposalsOfNoncurrentAssets
1271 Other (Income) Loss, Net Concept (Monetary) For Period Credit ifrs-full:OtherGainsLosses
1272 Adjusted EBITDA Concept (Monetary) For Period Credit cve:AdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortization
1273 Net Debt to Adjusted EBITDA Concept (Percent) For Period cve:NetDebtToAdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortization
1274 101250 - Disclosure - Long-term Debt and Capital Structure - Summary of Net Debt to Capitalization (Detail) Network

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1275 Implied Table Table

*

*

 implied:Table
1276 Disclosure Of Objectives Policies And Processes For Managing Capital [Abstract] Abstract ifrs-full:DisclosureOfObjectivesPoliciesAndProcessesForManagingCapitalAbstract
1277 Net Debt Concept (Monetary) As Of Credit ifrs-full:NetDebt
1278 Shareholders’ Equity Concept (Monetary) As Of Credit ifrs-full:Equity
1279 Debt and Shareholders' Equity, Net Concept (Monetary) As Of Credit cve:NetDebtAndEquity
1280 Net Debt to Capitalization Concept (Percent) For Period cve:NetDebtToCapitalization
1281 101260 - Disclosure - Contingent Payment - Summary of Contingent Payment (Detail) Network

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 http://www.cenovus.com/20181231/taxonomy/role/DisclosureContingentPaymentSummaryOfContingentPaymentDetail
1282 Implied Table Table

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*

 implied:Table
1283 Disclosure Of Contingent Liabilities In Business Combination [Abstract] Abstract ifrs-full:DisclosureOfContingentLiabilitiesInBusinessCombinationAbstract
1284 Contingent Payment, Beginning of Year Concept (Monetary) As Of Credit ifrs-full:ContingentLiabilitiesRecognisedInBusinessCombination
1285 Initial Recognition on Acquisition (Note 9) Concept (Monetary) For Period Credit ifrs-full:NewLiabilitiesContingentLiabilitiesRecognisedInBusinessCombination
1286 Re-measurement Concept (Monetary) For Period Debit cve:ReMeasurementOfContingentPayments
1287 Liabilities Settled or Payable Concept (Monetary) For Period Debit ifrs-full:SettledLiabilitiesContingentLiabilitiesRecognisedInBusinessCombination
1288 Contingent Payment, End of Year Concept (Monetary) As Of Credit ifrs-full:ContingentLiabilitiesRecognisedInBusinessCombination
1289 Less: Current Portion Concept (Monetary) As Of Credit cve:ContingentPaymentCurrent
1290 Long-Term Portion Concept (Monetary) As Of Credit cve:ContingentPaymentLongterm
1291 101270 - Disclosure - Contingent Payment - Additional Information (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureContingentPaymentAdditionalInformationDetail
1292 Implied Table Table

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 implied:Table
1293 Disclosure Of Contingent Liabilities In Business Combination [Abstract] Abstract ifrs-full:DisclosureOfContingentLiabilitiesInBusinessCombinationAbstract
1294 Contingent payable Concept (Monetary) For Period Debit ifrs-full:SettledLiabilitiesContingentLiabilitiesRecognisedInBusinessCombination
1295 101280 - Disclosure - Onerous Contract Provisions - Summary of Onerous Contract Provisions (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureOnerousContractProvisionsSummaryOfOnerousContractProvisionsDetail
1296 Implied Table Table

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*

 implied:Table
1297 Onerous Contracts Provision [Abstract] Abstract ifrs-full:OnerousContractsProvisionAbstract
1298 Onerous Contract Provisions, Beginning of Year Concept (Monetary) As Of Credit ifrs-full:OnerousContractsProvision
1299 Liabilities Incurred Concept (Monetary) For Period Credit cve:OnerousContractLiabilitiesIncurred
1300 Liabilities Settled Concept (Monetary) For Period Debit cve:OnerousContractLiabilitiesSettled
1301 Change in Assumptions Concept (Monetary) For Period Credit cve:OnerousContractIncreaseDecreaseInAssumptions
1302 Change in Discount Rate Concept (Monetary) For Period Credit cve:OnerousContractIncreaseDecreaseInDiscountRate
1303 Unwinding of Discount on Onerous Contract Provisions Concept (Monetary) For Period Credit cve:OnerousContractUnwindingOfDiscount
1304 Onerous Contract Provisions, End of Year Concept (Monetary) As Of Credit ifrs-full:OnerousContractsProvision
1305 Less: Current Portion Concept (Monetary) As Of Credit ifrs-full:ShorttermOnerousContractsProvision
1306 Long-Term Portion Concept (Monetary) As Of Credit ifrs-full:LongtermOnerousContractsProvision
1307 101290 - Disclosure - Onerous Contract Provisions - Additional information (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureOnerousContractProvisionsAdditionalInformationDetail
1308 Disclosure Of Other Provisions [Table] Table

*

*

 ifrs-full:DisclosureOfOtherProvisionsTable
1309 Classes of other provisions [axis] Axis ifrs-full:ClassesOfProvisionsAxis
1310 Other provisions [member] Member ifrs-full:OtherProvisionsMember
1311 Onerous Contracts Provision [Member] Member ifrs-full:OnerousContractsProvisionMember
1312 Range [axis] Axis ifrs-full:RangeAxis
1313 Ranges [member] Member ifrs-full:RangesMember
1314 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1315 Top of range [Member] Member ifrs-full:TopOfRangeMember
1316 Disclosure Of Other Provisions [Line Items] LineItems ifrs-full:DisclosureOfOtherProvisionsLineItems
1317 Credit-adjusted risk-free rate Concept (Percent) For Period cve:CreditAdjustedRiskFreeRate
1318 101300 - Disclosure - Onerous Contract Provisions - Summary Of Changes to Credit Adjusted Risk Free Rate or Estimated Sublease Recovery on Onerous Contract Provisions (Detail) Network

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*

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1319 Implied Table Table

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1320 Disclosure Of Other Provisions [Abstract] Abstract ifrs-full:DisclosureOfOtherProvisionsAbstract
1321 Credit-adjusted risk-free rate sensitivity range Concept (Percent) For Period cve:CreditAdjustedRiskFreeRateSensitivityRange
1322 Estimated sublease recovery sensitivity range Concept (Percent) For Period cve:EstimatedSubleaseRecoverySensitivityRange
1323 Credit-adjusted risk-free rate increase Concept (Monetary) For Period Debit cve:TheoreticalImpactToOnerousContractProvisionsFromIncreaseCreditAdjustedRiskFreeRateSensitivity
1324 Estimated sublease recovery increase Concept (Monetary) For Period Debit cve:TheoreticalImpactToOnerousContractProvisionsFromIncreaseEstimatedSubleaseRecoverySensitivity
1325 Credit-adjusted risk-free rate decrease Concept (Monetary) For Period Debit cve:TheoreticalImpactToOnerousContractProvisionsFromDecreaseCreditAdjustedRiskFreeRateSensitivity
1326 Estimated sublease recovery decrease Concept (Monetary) For Period Credit cve:TheoreticalImpactToOnerousContractProvisionsFromDecreaseEstimatedSubleaseRecoverySensitivity
1327 101310 - Disclosure - Decommissioning Liabilities - Summary of Decommissioning Provision (Detail) Network

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*

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1328 Implied Table Table

*

*

 implied:Table
1329 Provision For Decommissioning Restoration And Rehabilitation Costs [Abstract] Abstract ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCostsAbstract
1330 Decommissioning Liabilities, Beginning of Year Concept (Monetary) As Of Credit ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCosts
1331 Liabilities Incurred Concept (Monetary) For Period Credit ifrs-full:NewProvisionsOtherProvisions
1332 Liabilities Acquired Concept (Monetary) For Period Credit ifrs-full:AcquisitionsThroughBusinessCombinationsOtherProvisions
1333 Liabilities Settled Concept (Monetary) For Period Debit ifrs-full:ProvisionUsedOtherProvisions
1334 Liabilities Disposed (1) Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTransfersAndOtherChangesOtherProvisions
1335 Transfers (to) from Liabilities Related to Assets Held for Sale (Note 11) Concept (Monetary) For Period Debit ifrs-full:DecreaseThroughTransferToLiabilitiesIncludedInDisposalGroupsClassifiedAsHeldForSaleOtherProvisions
1336 Change in Estimated Future Cash Flows Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseInExistingProvisionsOtherProvisions
1337 Change in Discount Rate Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughChangeInDiscountRateOtherProvisions
1338 Unwinding of Discount on Decommissioning Liabilities Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughTimeValueOfMoneyAdjustmentOtherProvisions
1339 Foreign Currency Translation Concept (Monetary) For Period Credit cve:IncreaseDecreaseThroughForeignCurrencyTranslation
1340 Decommissioning Liabilities, End of Year Concept (Monetary) As Of Credit ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCosts
1341 101320 - Disclosure - Decommissioning Liabilities - Additional Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureDecommissioningLiabilitiesAdditionalInformationDetail
1342 Disclosure Of Other Provisions [Table] Table

*

*

 ifrs-full:DisclosureOfOtherProvisionsTable
1343 Range [axis] Axis ifrs-full:RangeAxis
1344 Ranges [member] Member ifrs-full:RangesMember
1345 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1346 Top of range [Member] Member ifrs-full:TopOfRangeMember
1347 Disclosure Of Other Provisions [Line Items] LineItems ifrs-full:DisclosureOfOtherProvisionsLineItems
1348 Estimated future cash flows required to settle the obligation Concept (Monetary) For Period Credit cve:UndiscountedCashOutflowRequiredToSettleObligation
1349 Credit-adjusted risk-free rate Concept (Percent) For Period cve:CreditAdjustedRiskFreeRate
1350 Inflation Rate Concept (Percent) As Of cve:InflationRate
1351 Settlement Of Decommissioning Liabilities Concept (Monetary) For Period Credit cve:ExpectedOutflowsOtherProvisions
1352 101330 - Disclosure - Decommissioning Liabilities - Summary of Changes to the Credit-Adjusted Risk-Free Rate or the Inflation Rate Impact on the Decommissioning Liabilities (Detail) Network

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1353 Disclosure Of Other Provisions [Table] Table

*

*

 ifrs-full:DisclosureOfOtherProvisionsTable
1354 Credit Adjusted Risk Free Rate And Inflation Rate Axis cve:CreditAdjustedRiskFreeRateAndInflationRateAxis
1355 Credit Adjusted Risk Free Rate And Inflation Rate Member cve:CreditAdjustedRiskFreeRateAndInflationRateDomain
1356 One percent increase [member] Member cve:OnePercentIncreaseMember
1357 One percent decrease [member] Member cve:OnePercentDecreaseMember
1358 Disclosure Of Other Provisions [Line Items] LineItems ifrs-full:DisclosureOfOtherProvisionsLineItems
1359 Credit-AdjustedRisk-FreeRate Concept (Monetary) For Period Credit cve:TheoreticalImpactToDecommissioningLiabilityFromIncreaseDecreaseCreditAdjustedRiskFreeRateSensitivity
1360 Inflation Rate Concept (Monetary) For Period Credit cve:TheoreticalImpactToDecommissioningLiabilityFromIncreaseDecreaseInflationRateSensitivity
1361 101340 - Disclosure - Other Liabilities - Summary of Other Liabilities (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureOtherLiabilitiesSummaryOfOtherLiabilitiesDetail
1362 Implied Table Table

*

*

 implied:Table
1363 Miscellaneous Noncurrent Liabilities [Abstract] Abstract ifrs-full:MiscellaneousNoncurrentLiabilitiesAbstract
1364 Employee Long-Term Incentives Concept (Monetary) As Of Credit cve:NonCurrentLiabilitiesFromShareBasedPaymentTransactions2011
1365 Pension and Other Post-Employment Benefit Plan (Note 27) Concept (Monetary) As Of Credit cve:NetLiabilitiesOfDefinedBenefitPlanAndOtherPostEmploymentBenefitPlan
1366 Other Concept (Monetary) As Of Credit cve:OtherNoncurrentLiabilitiesOther
1367 Other Liabilities Concept (Monetary) As Of Credit ifrs-full:OtherNoncurrentLiabilities
1368 101350 - Disclosure - Pensions and Other Post-Employment Benefits - Additional Information (Detail) Network

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*

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1369 Disclosure Of Defined Benefit Plans [Table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
1370 Defined benefit plans [axis] Axis ifrs-full:DefinedBenefitPlansAxis
1371 Defined benefit plans [member] Member ifrs-full:DefinedBenefitPlansMember
1372 Pension Benefits [Member] Member cve:PensionBenefitsMember
1373 OPEB [Member] Member cve:OtherPostEmploymentBenefitsMember
1374 Range [axis] Axis ifrs-full:RangeAxis
1375 Ranges [member] Member ifrs-full:RangesMember
1376 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1377 Top of range [Member] Member ifrs-full:TopOfRangeMember
1378 Statement Scenario Axis us-gaap:StatementScenarioAxis
1379 Scenario Unspecified Member us-gaap:ScenarioUnspecifiedDomain
1380 Scenario Forecast Member us-gaap:ScenarioForecastMember
1381 Disclosure Of Defined Benefit Plans [Line Items] LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1382 Maximum age for retired employees eligible for health care dental and life insurance benefits Concept (Decimal) As Of cve:MaximumAgeForRetiredEmployeesEligibleForHealthCareDentalAndLifeInsuranceBenefits
1383 Weighted average duration of the OPEB Concept (xbrli:durationItemType) For Period cve:WeightedAverageDurationOfDefinedBenefitObligations
1384 Defined benefit plan, equity securities allocation percentage Concept (Percent) For Period cve:EquityInstrumentsPercentageContributedToFairValueOfPlanAsset
1385 Defined benefit plan, fixed income assets allocation percentage Concept (Percent) For Period cve:DefinedBenefitPlanFixedIncomeAssetsAllocationPercentage
1386 Defined benefit plan, real estate assets allocation percentage Concept (Percent) For Period cve:DefinedBenefitPlanRealEstateAssetsAllocationPercentage
1387 Defined benefit plan, cash and cash equivalents allocation percentage Concept (Percent) For Period cve:CashAndCashEquivalentsPercentageContributedToFairValueOfPlanAssets
1388 Percentage of employees contribution under pension plan Concept (Percent) For Period cve:DefinedBenefitPlanEmployeeMinimumContributionPercentage
1389 Employer contribution Concept (Monetary) For Period Credit ifrs-full:EmployerContributions
1390 101360 - Disclosure - Pensions and Other Post-Employment Benefits - Summary of Defined Benefit and OPEB Plan Obligation and Funded Status (Detail) Network

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1391 Disclosure Of Net Defined Benefit Liability Asset [Table] Table

*

*

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1392 Defined benefit plans [axis] Axis ifrs-full:DefinedBenefitPlansAxis
1393 Defined benefit plans [member] Member ifrs-full:DefinedBenefitPlansMember
1394 Pension Benefits [Member] Member cve:PensionBenefitsMember
1395 OPEB [Member] Member cve:OtherPostEmploymentBenefitsMember
1396 Net defined benefit liability (asset) [axis] Axis ifrs-full:NetDefinedBenefitLiabilityAssetAxis
1397 Net defined benefit liability (asset) [member] Member ifrs-full:NetDefinedBenefitLiabilityAssetMember
1398 Present value of defined benefit obligation [Member] Member ifrs-full:PresentValueOfDefinedBenefitObligationMember
1399 Plan assets [Member] Member ifrs-full:PlanAssetsMember
1400 Disclosure Of Net Defined Benefit Liability Asset [Line Items] LineItems ifrs-full:DisclosureOfNetDefinedBenefitLiabilityAssetLineItems
1401 Defined Benefit Obligation, Beginning of Year Concept (Monetary) As Of Debit cve:NetLiabilitiesOfDefinedBenefitPlan
1402 Defined Benefit Obligation, Beginning of Year Concept (Monetary) As Of Credit cve:LiabilitiesOfOtherPostEmploymentBenefitPlan
1403 Fair Value of Plan Assets, Beginning of Year Concept (Monetary) As Of Debit ifrs-full:AssetsOfBenefitPlan
1404 Current Service Costs Concept (Monetary) For Period Credit ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
1405 Interest Income (Costs) Concept (Monetary) For Period Credit ifrs-full:InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
1406 Benefits Paid Concept (Monetary) For Period Credit ifrs-full:DecreaseThroughBenefitsPaidReimbursementRightsAtFairValue
1407 Employer Contributions Concept (Monetary) For Period Debit ifrs-full:ContributionsToPlanByEmployerNetDefinedBenefitLiabilityAsset
1408 Plan Participant Contributions Concept (Monetary) For Period Debit ifrs-full:ContributionsToPlanByPlanParticipantsNetDefinedBenefitLiabilityAsset
1409 Past Service Costs – Curtailments Concept (Monetary) For Period Credit ifrs-full:PastServiceCostNetDefinedBenefitLiabilityAsset
1410 Re-measurements: Abstract ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAssetAbstract
1411 (Gains) Losses from Experience Adjustments Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset
1412 (Gains) Losses from Changes in Demographic Assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetDefinedBenefitLiabilityAsset
1413 (Gains) Losses from Changes in Financial Assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
1414 Defined Benefit Obligation, End of Year Concept (Monetary) As Of Debit cve:NetLiabilitiesOfDefinedBenefitPlan
1415 Defined Benefit Obligation, End of Year Concept (Monetary) As Of Credit cve:LiabilitiesOfOtherPostEmploymentBenefitPlan
1416 Return on Plan Assets (Excluding Interest Income) Concept (Monetary) For Period Debit ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
1417 Fair Value of Plan Assets, End of Year Concept (Monetary) As Of Debit ifrs-full:AssetsOfBenefitPlan
1418 101370 - Disclosure - Pensions and Other Post-Employment Benefits - Summary of Pension and OPEB Costs (Detail) Network

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1419 Disclosure Of Defined Benefit Plans [Table] Table

*

*

 ifrs-full:DisclosureOfDefinedBenefitPlansTable
1420 Defined benefit plans [axis] Axis ifrs-full:DefinedBenefitPlansAxis
1421 Defined benefit plans [member] Member ifrs-full:DefinedBenefitPlansMember
1422 Pension Benefits [Member] Member cve:PensionBenefitsMember
1423 OPEB [Member] Member cve:OtherPostEmploymentBenefitsMember
1424 Disclosure Of Defined Benefit Plans [Line Items] LineItems ifrs-full:DisclosureOfDefinedBenefitPlansLineItems
1425 Current Service Costs Concept (Monetary) For Period Credit ifrs-full:CurrentServiceCostNetDefinedBenefitLiabilityAsset
1426 Past Service Costs – Curtailments Concept (Monetary) For Period Credit ifrs-full:PastServiceCostNetDefinedBenefitLiabilityAsset
1427 Net Settlement Costs Concept (Monetary) For Period Debit ifrs-full:GainsLossesArisingFromSettlementsNetDefinedBenefitLiabilityAsset
1428 Net Interest Costs Concept (Monetary) For Period Credit ifrs-full:InterestExpenseIncomeNetDefinedBenefitLiabilityAsset
1429 Re-measurements: Abstract ifrs-full:GainLossOnRemeasurementOfNetDefinedBenefitLiabilityAssetAbstract
1430 Return on Plan Assets (Excluding Interest Income) Concept (Monetary) For Period Debit ifrs-full:ReturnOnPlanAssetsNetDefinedBenefitLiabilityAsset
1431 (Gains) Losses from Experience Adjustments Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromExperienceAdjustmentsNetDefinedBenefitLiabilityAsset
1432 (Gains) Losses from Changes in Demographic Assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInDemographicAssumptionsNetDefinedBenefitLiabilityAsset
1433 (Gains) Losses from Changes in Financial Assumptions Concept (Monetary) For Period Debit ifrs-full:ActuarialGainsLossesArisingFromChangesInFinancialAssumptionsNetDefinedBenefitLiabilityAsset
1434 Defined Benefit Plan Cost (Recovery) Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedBenefitPlans
1435 Defined Contribution Plan Cost Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedContributionPlans
1436 Total Plan Cost Concept (Monetary) For Period Debit cve:PostemploymentBenefitExpenseDefinedBenefitAndDefinedContributionPlans
1437 101380 - Disclosure - Pensions and Other Post-Employment Benefits - Summary of Fair Value of the Plan Assets (Detail) Network

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1438 Implied Table Table

*

*

 implied:Table
1439 Disclosure Of Fair Value Of Plan Assets [Abstract] Abstract ifrs-full:DisclosureOfFairValueOfPlanAssetsAbstract
1440 Equity Funds Concept (Monetary) As Of Debit ifrs-full:EquityInstrumentsAmountContributedToFairValueOfPlanAssets
1441 Bond Funds Concept (Monetary) As Of Debit ifrs-full:DebtInstrumentsAmountContributedToFairValueOfPlanAssets
1442 Non-Invested Assets Concept (Monetary) As Of Debit cve:NoninvestedAssetsAmountContributedToFairValueOfPlanAssets
1443 Real Estate Funds Concept (Monetary) As Of Debit ifrs-full:PropertyAmountContributedToFairValueOfPlanAssets
1444 Cash and Cash Equivalents Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalentsAmountContributedToFairValueOfPlanAssets
1445 Total fair value Concept (Monetary) As Of Debit ifrs-full:PlanAssetsAtFairValue
1446 101390 - Disclosure - Pensions and Other Post-Employment Benefits - Summary of Principal Weighted Average Actuarial Assumptions Used to Determine Benefit Obligations and Expenses (Detail) Network

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1447 Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Table] Table

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*

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1448 Defined benefit plans [axis] Axis ifrs-full:DefinedBenefitPlansAxis
1449 Defined benefit plans [member] Member ifrs-full:DefinedBenefitPlansMember
1450 Pension Benefits [Member] Member cve:PensionBenefitsMember
1451 OPEB [Member] Member cve:OtherPostEmploymentBenefitsMember
1452 Disclosure Of Actuarial Assumptions [Line Items] LineItems cve:DisclosureOfActuarialAssumptionsLineItems
1453 Discount Rate Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfDiscountRates
1454 Future Salary Growth Rate Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreases
1455 Average Longevity (years) Concept (Decimal) As Of ifrs-full:ActuarialAssumptionOfMortalityRates
1456 Health Care Cost Trend Rate Concept (Percent) As Of ifrs-full:ActuarialAssumptionOfMedicalCostTrendRates
1457 101400 - Disclosure - Pensions and Other Post-Employment Benefits - Sensitivity of Defined Benefit and OPEB Obligation to Changes in Relevant Actuarial Assumptions (Detail) Network

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1458 Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Table] Table

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*

 ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsTable
1459 Actuarial assumptions [axis] Axis ifrs-full:ActuarialAssumptionsAxis
1460 Actuarial assumptions [member] Member ifrs-full:ActuarialAssumptionsMember
1461 Discount Rate [Member] Member ifrs-full:ActuarialAssumptionOfDiscountRatesMember
1462 Future Salary Growth Rate [Member] Member ifrs-full:ActuarialAssumptionOfExpectedRatesOfSalaryIncreasesMember
1463 Health Care Cost Trend Rate [Member] Member ifrs-full:ActuarialAssumptionOfMedicalCostTrendRatesMember
1464 One Year Change in Assumed Life Expectancy [Member] Member ifrs-full:ActuarialAssumptionOfMortalityRatesMember
1465 Disclosure Of Sensitivity Analysis For Actuarial Assumptions [Line Items] LineItems ifrs-full:DisclosureOfSensitivityAnalysisForActuarialAssumptionsLineItems
1466 Increase Concept (Monetary) As Of Credit ifrs-full:IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleIncreaseInActuarialAssumption
1467 Decrease Concept (Monetary) As Of Credit ifrs-full:IncreaseDecreaseInDefinedBenefitObligationDueToReasonablyPossibleDecreaseInActuarialAssumption
1468 Sensitivity Range - One percent change Concept (Percent) As Of ifrs-full:PercentageOfReasonablyPossibleIncreaseInActuarialAssumption
1469 Sensitivity Range - One year change in expected life Concept (Integer) As Of cve:ActuarialAssumptionOfLifeExpectancy
1470 101410 - Disclosure - Share Capital - Additional Information (Detail) Network

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1471 Disclosure Of Classes Of Share Capital [Table] Table

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*

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1472 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
1473 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
1474 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
1475 Classes of share capital [axis] Axis ifrs-full:ClassesOfShareCapitalAxis
1476 Share capital [member] Member ifrs-full:ClassesOfShareCapitalMember
1477 Preferred Shares [Member] Member ifrs-full:PreferenceSharesMember
1478 Stock Option Plan [member] Member cve:StockOptionPlanMember
1479 Disclosure of classes of share capital [Line Items] LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
1480 Maximum percentage of preferred stock upon issuance or outstanding of common stock Concept (Percent) For Period cve:PercentageOfOutstandingSharesAuthorizedForIssuance
1481 Number of common shares authorized Concept (Text/String) For Period cve:NumberOfCommonSharesAuthorised
1482 Number of common share financing through bought-deal Concept (Shares) As Of ifrs-full:NumberOfSharesIssuedAndFullyPaid
1483 Gross proceeds from bought-deal offering Concept (Monetary) For Period Debit cve:ProceedsFromIssuingSharesBeforeShareIssueRelatedCost
1484 Net proceeds from bought-deal offering Concept (Monetary) For Period Debit ifrs-full:ProceedsFromIssuingShares
1485 Share issuance costs Concept (Monetary) For Period Debit ifrs-full:ShareIssueRelatedCost
1486 Consideration transferred as common shares Concept (Decimal) As Of ifrs-full:NumberOfInstrumentsOrInterestsIssuedOrIssuable
1487 Percentage of owned outstanding shares Concept (Percent) For Period cve:MaximumOwnershipPercentageToNominateBoardMembersOrVoteAgainstManagementRecommendations
1488 Shares outstanding Concept (Shares) As Of ifrs-full:NumberOfSharesOutstanding
1489 Shares available for future issuance Concept (Shares) As Of ifrs-full:SharesReservedForIssueUnderOptionsAndContractsForSaleOfShares
1490 101420 - Disclosure - Share Capital - Summary of Share Capital (Detail) Network

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 http://www.cenovus.com/20181231/taxonomy/role/DisclosureShareCapitalSummaryOfShareCapitalDetail
1491 Disclosure Of Classes Of Share Capital [Table] Table

*

*

 ifrs-full:DisclosureOfClassesOfShareCapitalTable
1492 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
1493 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
1494 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
1495 Disclosure of classes of share capital [Line Items] LineItems ifrs-full:DisclosureOfClassesOfShareCapitalLineItems
1496 Outstanding, Beginning of Year Concept (Shares) As Of ifrs-full:NumberOfSharesOutstanding
1497 Common Shares Issued, Net of Issuance Costs and Tax Concept (Shares) As Of ifrs-full:NumberOfSharesIssuedAndFullyPaid
1498 Common Shares Issued to ConocoPhillips Concept (Shares) For Period cve:SharesIssuedDuringPeriodForAcquisitionShares
1499 Outstanding, End of Year Concept (Shares) As Of ifrs-full:NumberOfSharesOutstanding
1500 Outstanding, Beginning of Year Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
1501 Common Shares Issued, Net of Issuance Costs and Tax Concept (Monetary) For Period Credit cve:CommonSharesIssuedNetOfIssuanceCostsAndTax
1502 Common Shares Issued to ConocoPhillips Concept (Monetary) For Period Credit cve:SharesIssuedDuringPeriodForAcquisitionValues
1503 Outstanding, End of Year Concept (Monetary) As Of Credit ifrs-full:IssuedCapital
1504 101430 - Disclosure - Share Capital - Schedule of Paid in Surplus Includes Stock Based Compensation Expense (Detail) Network

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*

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1505 Disclosure Of Reserves Within Equity [Table] Table

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*

 ifrs-full:DisclosureOfReservesWithinEquityTable
1506 Classes of share capital [axis] Axis ifrs-full:ClassesOfShareCapitalAxis
1507 Share capital [member] Member ifrs-full:ClassesOfShareCapitalMember
1508 Pre-Arrangement Earnings [member] Member cve:PrearrangementEarningsMember
1509 Stock-Based Compensation [member] Member cve:StockBasedCompensationMember
1510 Disclosure of reserves within equity [line items] LineItems ifrs-full:DisclosureOfReservesWithinEquityLineItems
1511 Beginning Balance Concept (Monetary) As Of Credit ifrs-full:AdditionalPaidinCapital
1512 Stock-Based Compensation Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseFromSharebasedPaymentTransactionsWithEmployees
1513 Ending Balance Concept (Monetary) As Of Credit ifrs-full:AdditionalPaidinCapital
1514 101440 - Disclosure - Accumulated Other Comprehensive Income (Loss) - Schedule of Accumulated Other Comprehensive Income (Loss) (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureAccumulatedOtherComprehensiveIncomeLossScheduleOfAccumulatedOtherComprehensiveIncomeLossDetail
1515 Disclosure Of Accumulated Other Comprehensive Income Loss [Table] Table

*

*

 cve:DisclosureOfAccumulatedOtherComprehensiveIncomeLossTable
1516 Components of equity [axis] Axis ifrs-full:ComponentsOfEquityAxis
1517 Equity [member] Member ifrs-full:EquityMember
1518 Defined Benefit Pension Plan [Member] Member cve:DefinedBenefitPensionPlanMember
1519 Foreign Currency Translation Adjustment [Member] Member ifrs-full:ReserveOfExchangeDifferencesOnTranslationMember
1520 Private Equity Instruments [Member] Member ifrs-full:ReserveOfGainsAndLossesFromInvestmentsInEquityInstrumentsMember
1521 Disclosure of accumulated other comprehensive income loss [line items] LineItems cve:DisclosureOfAccumulatedOtherComprehensiveIncomeLossLineItems
1522 Beginning Balance Concept (Monetary) As Of Credit ifrs-full:AccumulatedOtherComprehensiveIncome
1523 Other Comprehensive Income (Loss), Before Tax Concept (Monetary) For Period Credit ifrs-full:OtherComprehensiveIncomeBeforeTax
1524 Income Tax Concept (Monetary) For Period ifrs-full:IncomeTaxRelatingToComponentsOfOtherComprehensiveIncome
1525 Ending Balance Concept (Monetary) As Of Credit ifrs-full:AccumulatedOtherComprehensiveIncome
1526 101450 - Disclosure - Stock-Based Compensation Plans - Additional Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureStockBasedCompensationPlansAdditionalInformationDetail
1527 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
1528 Maturity [axis] Axis ifrs-full:MaturityAxis
1529 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1530 Later than one year [Member] Member ifrs-full:LaterThanOneYearMember
1531 Later than two years [Member] Member ifrs-full:LaterThanTwoYearsAndNotLaterThanThreeYearsMember
1532 Later than three years [Member] Member ifrs-full:LaterThanThreeYearsMember
1533 Later than four years and not later than five years [Member] Member ifrs-full:LaterThanFourYearsAndNotLaterThanFiveYearsMember
1534 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1535 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1536 NSRs [Member] Member cve:NetSettlementRightsMember
1537 TSARs [Member] Member cve:TandemStockAppreciationRightsMember
1538 PSUs [Member] Member cve:PerformanceShareUnitsMember
1539 RSUs [Member] Member cve:RestrictedShareUnitsMember
1540 DSUs [Member] Member cve:DeferredShareUnitsMember
1541 DSUs Option One [Member] Member cve:DeferredShareUnitsOptionOneMember
1542 DSUs Option Two [Member] Member cve:DeferredShareUnitsOptionTwoMember
1543 DSUs Option Three [Member] Member cve:DeferredShareUnitsOptionThreeMember
1544 Disclosure of terms and conditions of share-based payment arrangement [Line Items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
1545 Percentage of options exercisable Concept (Percent) For Period cve:PercentageOfShareOptionsExercisableInSharebasedPaymentArrangement
1546 Options expiration term Concept (xbrli:durationItemType) For Period cve:TermOfShareOptionsInSharebasedPaymentArrangement
1547 Weighted average unit fair value of granted Concept (Monetary) As Of Credit ifrs-full:WeightedAverageFairValueAtMeasurementDateShareOptionsGranted
1548 Percentage of units vesting Concept (Percent) For Period cve:PercentageOfOtherEquityInstrumentsVestingInSharebasedPaymentArrangement
1549 Vesting period Concept (xbrli:durationItemType) For Period cve:SharebasedPaymentArrangementVestingPeriod
1550 Liabilities from share based payment Concept (Monetary) As Of Credit ifrs-full:LiabilitiesFromSharebasedPaymentTransactions2011
1551 Intrinsic value of vested Concept (Monetary) As Of Credit ifrs-full:IntrinsicValueOfLiabilitiesFromSharebasedPaymentTransactionsForWhichCounterpartysRightToCashOrOtherAssetsVested2011
1552 Number of Deferred Share Unit Plans Concept (Decimal) For Period cve:NumberOfDeferredShareUnitPlans
1553 Percentage of annual bonus award to convert into DSUs Concept (Percent) For Period cve:PercentageOfBonusAwardConversionToDeferredShareUnits
1554 101460 - Disclosure - Stock-Based Compensation Plans - Summary of Assumptions Used to Determine Fair Value of Options Granted (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureStockBasedCompensationPlansSummaryOfAssumptionsUsedToDetermineFairValueOfOptionsGrantedDetail
1555 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
1556 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1557 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1558 NSRs [Member] Member cve:NetSettlementRightsMember
1559 Disclosure of terms and conditions of share-based payment arrangement [Line Items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
1560 Risk-Free Interest Rate Concept (Percent) For Period ifrs-full:DescriptionOfRiskFreeInterestRateShareOptionsGranted
1561 Expected Dividend Yield Concept (Percent) For Period ifrs-full:ExpectedDividendAsPercentageShareOptionsGranted
1562 Expected Volatility Concept (Percent) For Period ifrs-full:DescriptionOfExpectedVolatilityShareOptionsGranted
1563 Expected Life Concept (Decimal) For Period ifrs-full:DescriptionOfOptionLifeShareOptionsGranted
1564 101470 - Disclosure - Stock-Based Compensation Plans - Summary of Stock Option Activity and Related Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureStockBasedCompensationPlansSummaryOfStockOptionActivityAndRelatedInformationDetail
1565 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table] Table

*

*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
1566 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1567 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1568 NSRs [Member] Member cve:NetSettlementRightsMember
1569 PSUs [Member] Member cve:PerformanceShareUnitsMember
1570 RSUs [Member] Member cve:RestrictedShareUnitsMember
1571 DSUs [Member] Member cve:DeferredShareUnitsMember
1572 Categories of related parties [axis] Axis ifrs-full:CategoriesOfRelatedPartiesAxis
1573 Entity's total for related parties [member] Member ifrs-full:EntitysTotalForRelatedPartiesMember
1574 Director [Member] Member ifrs-full:KeyManagementPersonnelOfEntityOrParentMember
1575 Disclosure of terms and conditions of share-based payment arrangement [Line Items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
1576 Number of Share Options Outstanding, Beginning of Year Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
1577 Number of Share Options, Granted Concept (Decimal) For Period ifrs-full:NumberOfShareOptionsGrantedInSharebasedPaymentArrangement
1578 Number of Share Options, Forfeited Concept (Decimal) For Period ifrs-full:NumberOfShareOptionsForfeitedInSharebasedPaymentArrangement
1579 Number of Share Options, Expired Concept (Decimal) For Period ifrs-full:NumberOfShareOptionsExpiredInSharebasedPaymentArrangement
1580 Number of Share Options Outstanding, End of Year Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
1581 Weighted Average Exercise Price, Outstanding, Beginning of Year Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement
1582 Weighted Average Exercise Price, Granted Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfShareOptionsGrantedInSharebasedPaymentArrangement
1583 Weighted Average Exercise Price, Forfeited Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfShareOptionsForfeitedInSharebasedPaymentArrangement
1584 Weighted Average Exercise Price, Expired Concept (Monetary) For Period ifrs-full:WeightedAverageExercisePriceOfShareOptionsExpiredInSharebasedPaymentArrangement
1585 Weighted Average Exercise Price, Outstanding, End of Year Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement
1586 Number of Share Units, Outstanding, Beginning of Year Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
1587 Number of Share Units, Granted Concept (Decimal) For Period ifrs-full:NumberOfInstrumentsOtherEquityInstrumentsGranted
1588 Number of Share Units, Vested and Paid Out Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsExercisedOrVestedInSharebasedPaymentArrangement
1589 Number of Share Units, Cancelled Concept (Decimal) For Period ifrs-full:NumberOfOtherEquityInstrumentsForfeitedInSharebasedPaymentArrangement
1590 Number of Share Units, Units in Lieu of Dividends Concept (Decimal) For Period cve:NumberOfOtherEquityInstrumentsIssuedInLieuOfDividendsInSharebasedPaymentArrangement
1591 Number of Share Units, Redeemed Concept (Decimal) For Period cve:NumberOfOtherEquityInstrumentsRedeemedSharebasedPaymentArrangement
1592 Number of Share Units, Outstanding, End of Year Concept (Decimal) As Of ifrs-full:NumberOfOtherEquityInstrumentsOutstandingInSharebasedPaymentArrangement
1593 101480 - Disclosure - Stock-Based Compensation Plans - Summary of Options Outstanding and Exercisable by Range of Exercise Price (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureStockBasedCompensationPlansSummaryOfOptionsOutstandingAndExercisableByRangeOfExercisePriceDetail
1594 Disclosure Of Range Of Exercise Prices Of Outstanding Share Options [Table] Table

*

*

 ifrs-full:DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable
1595 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1596 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1597 NSRs [Member] Member cve:NetSettlementRightsMember
1598 Ranges of exercise prices for outstanding share options [axis] Axis ifrs-full:RangesOfExercisePricesForOutstandingShareOptionsAxis
1599 Ranges of exercise prices for outstanding share options [member] Member ifrs-full:RangesOfExercisePricesForOutstandingShareOptionsMember
1600 5.00 to 9.99 [Member] Member cve:FivePointZeroZeroToNinePointNineNineMember
1601 10.00 to 14.99 [Member] Member cve:TenPointZeroZeroToFourteenPointNineNineMember
1602 15.00 to 19.99 [Member] Member cve:FifteenPointZeroZeroToNineteenPointNineNineMember
1603 20.00 to 24.99 [Member] Member cve:TwentyPointZeroZeroToTwentyFourPointNineNineMember
1604 25.00 to 29.99 [Member] Member cve:TwentyFivePointZeroZeroToTwentyNinePointNineNineMember
1605 30.00 to 34.99 [Member] Member cve:ThirtyPointZeroZeroToThirtyFourPointNineNineMember
1606 35.00 to 39.99 [Member] Member cve:ThirtyFivePointZeroZeroToThirtyNinePointNineNineMember
1607 Disclosure of range of exercise prices of outstanding share options [Line Items] LineItems ifrs-full:DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems
1608 Outstanding Number Concept (Decimal) As Of ifrs-full:NumberOfOutstandingShareOptions
1609 Outstanding Weighted Average Remaining Contractual Life Concept (Decimal) As Of ifrs-full:WeightedAverageRemainingContractualLifeOfOutstandingShareOptions
1610 Outstanding Weighted Average Exercise Price Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsOutstandingInSharebasedPaymentArrangement
1611 Exercisable Number Concept (Decimal) As Of ifrs-full:NumberOfShareOptionsExercisableInSharebasedPaymentArrangement
1612 Exercisable Weighted Average Exercise Price Concept (Monetary) As Of ifrs-full:WeightedAverageExercisePriceOfShareOptionsExercisableInSharebasedPaymentArrangement
1613 101490 - Disclosure - Stock-Based Compensation Plans - Summary of Options Outstanding and Exercisable by Range of Exercise Price (Parenthetical) (Detail) Network

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1614 Disclosure Of Range Of Exercise Prices Of Outstanding Share Options [Table] Table

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*

 ifrs-full:DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsTable
1615 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1616 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1617 NSRs [Member] Member cve:NetSettlementRightsMember
1618 Range [axis] Axis ifrs-full:RangeAxis
1619 Ranges [member] Member ifrs-full:RangesMember
1620 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1621 Top of range [Member] Member ifrs-full:TopOfRangeMember
1622 Ranges of exercise prices for outstanding share options [axis] Axis ifrs-full:RangesOfExercisePricesForOutstandingShareOptionsAxis
1623 Ranges of exercise prices for outstanding share options [member] Member ifrs-full:RangesOfExercisePricesForOutstandingShareOptionsMember
1624 5.00 to 9.99 [Member] Member cve:FivePointZeroZeroToNinePointNineNineMember
1625 10.00 to 14.99 [Member] Member cve:TenPointZeroZeroToFourteenPointNineNineMember
1626 15.00 to 19.99 [Member] Member cve:FifteenPointZeroZeroToNineteenPointNineNineMember
1627 20.00 to 24.99 [Member] Member cve:TwentyPointZeroZeroToTwentyFourPointNineNineMember
1628 25.00 to 29.99 [Member] Member cve:TwentyFivePointZeroZeroToTwentyNinePointNineNineMember
1629 30.00 to 34.99 [Member] Member cve:ThirtyPointZeroZeroToThirtyFourPointNineNineMember
1630 35.00 to 39.99 [Member] Member cve:ThirtyFivePointZeroZeroToThirtyNinePointNineNineMember
1631 Disclosure of range of exercise prices of outstanding share options [Line Items] LineItems ifrs-full:DisclosureOfRangeOfExercisePricesOfOutstandingShareOptionsLineItems
1632 Options outstanding, exercise price Concept (Monetary) As Of ifrs-full:ExercisePriceOfOutstandingShareOptions
1633 101500 - Disclosure - Stock-Based Compensation Plans - Summary of Stock-Based Compensation (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureStockBasedCompensationPlansSummaryOfStockBasedCompensationDetail
1634 Disclosure Of Terms And Conditions Of Sharebased Payment Arrangement [Table] Table

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*

 ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementTable
1635 Types of share-based payment arrangements [axis] Axis ifrs-full:TypesOfSharebasedPaymentArrangementsAxis
1636 Share-based payment arrangements [member] Member ifrs-full:SharebasedPaymentArrangementsMember
1637 NSRs [Member] Member cve:NetSettlementRightsMember
1638 TSARs [Member] Member cve:TandemStockAppreciationRightsMember
1639 PSUs [Member] Member cve:PerformanceShareUnitsMember
1640 RSUs [Member] Member cve:RestrictedShareUnitsMember
1641 DSUs [Member] Member cve:DeferredShareUnitsMember
1642 Disclosure of terms and conditions of share-based payment arrangement [Line Items] LineItems ifrs-full:DisclosureOfTermsAndConditionsOfSharebasedPaymentArrangementLineItems
1643 Stock-Based Compensation Expense Concept (Monetary) For Period Debit ifrs-full:ExpenseFromSharebasedPaymentTransactionsWithEmployees
1644 Stock-Based Compensation Expense (Recovery) Concept (Monetary) For Period Debit cve:ShareBasedPaymentTransactionsWithEmployeesRecordedAsExpense
1645 Stock-Based Compensation Costs Capitalized Concept (Monetary) For Period Debit cve:ExpenseFromShareBasedPaymentTransactionsInWhichGoodsOrServicesReceivedQualifiedForRecognitionAsAssets
1646 Total Stock-Based Compensation Concept (Monetary) As Of Debit cve:StockBasedCompensations
1647 101510 - Disclosure - Employee Salaries and Benefit Expenses - Summary of Employee Salaries and Benefit Expenses (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureEmployeeSalariesAndBenefitExpensesSummaryOfEmployeeSalariesAndBenefitExpensesDetail
1648 Implied Table Table

*

*

 implied:Table
1649 Classes Of Employee Benefits Expense [Abstract] Abstract ifrs-full:ClassesOfEmployeeBenefitsExpenseAbstract
1650 Salaries, Bonuses and Other Short-Term Employee Benefits Concept (Monetary) For Period Debit ifrs-full:ShorttermEmployeeBenefitsExpense
1651 Defined Contribution Pension Plan Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedContributionPlans
1652 Defined Benefit Pension Plan and OPEB Concept (Monetary) For Period Debit ifrs-full:PostemploymentBenefitExpenseDefinedBenefitPlans
1653 Stock-Based Compensation Expense (Note 30) Concept (Monetary) For Period Debit cve:ShareBasedPaymentTransactionsWithEmployeesRecordedAsExpense
1654 Termination Benefits Concept (Monetary) For Period Debit ifrs-full:TerminationBenefitsExpense
1655 Employee Salaries and Benefit Expenses Concept (Monetary) For Period Debit ifrs-full:EmployeeBenefitsExpense
1656 101520 - Disclosure - Related Party Transactions - Summary of Key Management Compensation (Detail) Network

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 http://www.cenovus.com/20181231/taxonomy/role/DisclosureRelatedPartyTransactionsSummaryOfKeyManagementCompensationDetail
1657 Implied Table Table

*

*

 implied:Table
1658 Disclosure Of Transactions Between Related Parties [Abstract] Abstract ifrs-full:DisclosureOfTransactionsBetweenRelatedPartiesAbstract
1659 Salaries, Director Fees and Short-Term Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationShorttermEmployeeBenefits
1660 Termination Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationTerminationBenefits
1661 Post-Employment Benefits Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationPostemploymentBenefits
1662 Stock-Based Compensation Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensationSharebasedPayment
1663 Total compensation paid or payable Concept (Monetary) For Period Debit ifrs-full:KeyManagementPersonnelCompensation
1664 101530 - Disclosure - Financial Instruments - Additional information (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsAdditionalInformationDetail
1665 Disclosure Of Financial Instruments [Table] Table

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*

 ifrs-full:DisclosureOfFinancialInstrumentsTable
1666 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
1667 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
1668 Level 2 of Fair Value Hierarchy [Member] Member ifrs-full:Level2OfFairValueHierarchyMember
1669 Level 3 of Fair Value Hierarchy [Member] Member ifrs-full:Level3OfFairValueHierarchyMember
1670 Items of contingent liabilities [axis] Axis ifrs-full:ItemsOfContingentLiabilitiesAxis
1671 Items of contingent liabilities [member] Member ifrs-full:ItemsOfContingentLiabilitiesMember
1672 WCS Forward Prices [Member] Member cve:WesternCanadianSelectForwardPricingMember
1673 WTI Option Volatility [Member] Member cve:WestTexasIntermediateOptionVolatilityMember
1674 U.S. to Canadian Dollar Foreign Exchange Average Rate Volatility Contingent Payment [Member] Member cve:ForeignExchangeAverageVolatilityRateContingentMember
1675 Disclosure of detailed information about financial instruments [Line Items] LineItems ifrs-full:DisclosureOfFinancialInstrumentsLineItems
1676 Debt, carrying value Concept (Monetary) As Of Credit ifrs-full:Borrowings
1677 Debt, fair value Concept (Monetary) As Of Credit cve:FairValueDebtCarriedAtAmortizedCost
1678 Change in fair value of private equity instruments Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInFairValueMeasurementAssets
1679 Cash collateral for risk management contracts price change Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsPledgedAsCollateralForLiabilitiesOrContingentLiabilities
1680 Discounted Credit adjusted risk free rate Concept (Percent) For Period cve:ContingentPaymentCreditAdjustedRiskFreeRate
1681 Estimated fair value of contingent payment Concept (Monetary) As Of Credit ifrs-full:ContingentLiabilitiesRecognisedInBusinessCombination
1682 Average forward price for Western Canadian Select Crude Oil for the remaining term Concept (Decimal) As Of cve:AverageForwardPriceOfCrudeOilForRemainingTerm
1683 Average volatility contingent payment percentage Concept (Percent) For Period cve:OptionVolatility
1684 Average volatility contingent payment percentage Concept (Percent) For Period cve:ForeignExchangeRateVolatility
1685 101540 - Disclosure - Financial Instruments - Reconciliation of Changes in the Fair Value of Available for Sale Financial Assets (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsReconciliationOfChangesInFairValueOfAvailableForSaleFinancialAssetsDetail
1686 Disclosure Of Fair Value Measurement Of Assets [Table] Table

*

*

 ifrs-full:DisclosureOfFairValueMeasurementOfAssetsTable
1687 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
1688 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
1689 Level 3 of Fair Value Hierarchy [Member] Member ifrs-full:Level3OfFairValueHierarchyMember
1690 Disclosure of fair value measurement of assets [Line Items] LineItems ifrs-full:DisclosureOfFairValueMeasurementOfAssetsLineItems
1691 Fair Value, Beginning of Year Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValue
1692 Net Acquisition of Investments Concept (Monetary) For Period Debit cve:NetAcquisitionOfInvestments
1693 Change in Fair Value Concept (Monetary) For Period Debit ifrs-full:IncreaseDecreaseInFairValueMeasurementAssets
1694 Fair Value, End of Year Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValue
1695 101550 - Disclosure - Financial Instruments - Summary of Urealized Risk Management Positions (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsSummaryOfUrealizedRiskManagementPositionsDetail
1696 Disclosure Of Recurring Fair Value Measurement Of Assets And Liabilities [Table] Table

*

*

 cve:DisclosureOfRecurringFairValueMeasurementOfAssetsAndLiabilitiesTable
1697 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
1698 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
1699 Level 2 of Fair Value Hierarchy [Member] Member ifrs-full:Level2OfFairValueHierarchyMember
1700 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1701 Risks [member] Member ifrs-full:TypesOfRisksMember
1702 Interest rate swap contract [Member] Member ifrs-full:InterestRateSwapContractMember
1703 Commodity Price Risk [Member] Member ifrs-full:CommodityPriceRiskMember
1704 Currency risk [Member] Member ifrs-full:CurrencyRiskMember
1705 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1706 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1707 Crude Oil Contracts [Member] Member cve:CrudeOilContractsMember
1708 Disclosure Of Recurring Fair Value Measurement Of Assets And Liabilities [Line Items] LineItems cve:DisclosureOfRecurringFairValueMeasurementOfAssetsAndLiabilitiesLineItems
1709 Risk Management Asset Concept (Monetary) As Of Debit ifrs-full:FinancialAssetsAtFairValue
1710 Risk Management Liability Concept (Monetary) As Of Credit ifrs-full:FinancialLiabilitiesAtFairValue
1711 Risk Management Net Concept (Monetary) As Of Debit cve:FairValueOfDerivativeFinancialInstrumentsNet
1712 101560 - Disclosure - Financial Instruments - Summary of Fair Value Hierarchy for Risk Management Assets and Liabilities Carried at Fair Value (Detail) Network

*

*

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1713 Disclosure Of Levels Of Fair Value Hierarchy [Table] Table

*

*

 cve:DisclosureOfLevelsOfFairValueHierarchyTable
1714 Levels of fair value hierarchy [axis] Axis ifrs-full:LevelsOfFairValueHierarchyAxis
1715 All levels of fair value hierarchy [member] Member ifrs-full:AllLevelsOfFairValueHierarchyMember
1716 Level 2 of Fair Value Hierarchy [Member] Member ifrs-full:Level2OfFairValueHierarchyMember
1717 Disclosure Of Levels Of Fair Value Hierarchy [Line Items] LineItems cve:DisclosureOfLevelsOfFairValueHierarchyLineItems
1718 Fair Value of Risk Management Assets and Liabilities Concept (Monetary) As Of Debit cve:FairValueOfDerivativeFinancialInstrumentsNet
1719 101570 - Disclosure - Financial Instruments - Reconciliation of Changes in the Fair Value of Cenovus's Risk Management Assets and Liabilities (Detail) Network

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1720 Implied Table Table

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*

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1722 Fair Value of Contracts, Beginning of Year Concept (Monetary) As Of Debit cve:FairValueOfDerivativeFinancialInstrumentsNet
1723 Fair Value of Contracts Realized During the Year Concept (Monetary) For Period Credit cve:SettlementsFairValueMeasurementAssetsLiabilitiesIncludingDiscontinuedOperations
1724 Change in Fair Value of Contracts in Place at Beginning of Year and Contracts Entered Into During the Year Concept (Monetary) For Period Credit cve:GainsLossesOnChangeInFairValueOfContracts
1725 Unamortized (Amortized) Premium on Put Options Concept (Monetary) For Period Credit cve:UnamortizedAmortizedPremiumOnPutOptions
1726 Unrealized Foreign Exchange Gain (Loss) on U.S. Dollar Contracts Concept (Monetary) For Period Debit cve:ChangeInFairValueOfDerivativeFinancialInstrumentsFromForeignExchange
1727 Fair Value of Contracts, End of Year Concept (Monetary) As Of Debit cve:FairValueOfDerivativeFinancialInstrumentsNet
1728 101580 - Disclosure - Financial Instruments - Reconciliation of Changes in the Fair Value of Cenovus's Risk Management Assets and Liabilities (Parenthetical) (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsReconciliationOfChangesInFairValueOfCenovusSRiskManagementAssetsAndLiabilitiesParentheticalDetail
1729 Implied Table Table

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*

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1730 Reconciliation Of Changes In Fair Value Measurement Assets Liabilities [Abstract] Abstract cve:ReconciliationOfChangesInFairValueMeasurementAssetsLiabilitiesAbstract
1731 Realized (Gain) Loss Concept (Monetary) For Period Credit cve:GainsLossesOnChangeInFairValueOfDerivativesDiscontinuedOperations
1732 101590 - Disclosure - Financial Instruments - Summary of Offsetting Risk Management Positions (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsSummaryOfOffsettingRiskManagementPositionsDetail
1733 Implied Table Table

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1734 Disclosure Of Offsetting Of Financial Assets Liabilities [Abstract] Abstract cve:DisclosureOfOffsettingOfFinancialAssetsLiabilitiesAbstract
1735 Gross Amount, Risk Management Asset Concept (Monetary) As Of Debit ifrs-full:GrossFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1736 Amount Offset, Risk Management Asset Concept (Monetary) As Of Credit ifrs-full:GrossFinancialLiabilitiesSetOffAgainstFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1737 Net Amount per Consolidated Financial Statements, Risk Management Asset Concept (Monetary) As Of Debit ifrs-full:NetFinancialAssetsSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1738 Gross Amount, Risk Management Liabilities Concept (Monetary) As Of Credit ifrs-full:GrossFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1739 Amount Offset, Risk Management Liabilities Concept (Monetary) As Of Debit ifrs-full:GrossFinancialAssetsSetOffAgainstFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1740 Net Amount per Consolidated Financial Statements, Risk Management Liabilities Concept (Monetary) As Of Credit ifrs-full:NetFinancialLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1741 Gross Amount, Risk Management Net Concept (Monetary) For Period Debit cve:GrossFinancialAssetsLiabilitiesNetSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1742 Amount Offset, Risk Management Net Concept (Monetary) For Period Debit cve:GrossFinancialAssetsLiabilitiesNetSetOffAgainstFinancialAssetsLiabilitiesSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1743 Net Amount per Consolidated Financial Statements, Risk Management Net Concept (Monetary) For Period Debit cve:NetFinancialAssetsLiabilitiesNetSubjectToOffsettingEnforceableMasterNettingArrangementsOrSimilarAgreements
1744 101600 - Disclosure - Financial Instruments - Summary of Changes in Inputs to Option Pricing Model, Resulted in Unrealized Gains (Losses) Impacting Earnings Before Income Tax (Detail) Network

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*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureFinancialInstrumentsSummaryOfChangesInInputsToOptionPricingModelResultedInUnrealizedGainsLossesImpactingEarningsBeforeIncomeTaxDetail
1745 Disclosure Of Sensitivity Of Fair Value Measurement To Changes In Unobservable Inputs Liabilities [Table] Table

*

*

 cve:DisclosureOfSensitivityOfFairValueMeasurementToChangesInUnobservableInputsLiabilitiesTable
1746 Items of contingent liabilities [axis] Axis ifrs-full:ItemsOfContingentLiabilitiesAxis
1747 Items of contingent liabilities [member] Member ifrs-full:ItemsOfContingentLiabilitiesMember
1748 WCS Forward Prices [Member] Member cve:WesternCanadianSelectForwardPricingMember
1749 WTI Option Volatility [Member] Member cve:WestTexasIntermediateOptionVolatilityMember
1750 Foreign Exchange Volatility Rate [Member] Member cve:ForeignExchangeVolatilityRateMember
1751 Disclosure Of Sensitivity Of Fair Value Measurement To Changes In Unobservable Inputs Liabilities [Line Items] LineItems cve:DisclosureOfSensitivityOfFairValueMeasurementToChangesInUnobservableInputsLiabilitiesLineItems
1752 Sensitivity Price Range Concept (Percent) For Period cve:ContingentLiabilitiesSensitivityPriceRange
1753 Sensitivity Range Concept (Percent) For Period cve:ContingentLiabilitiesSensitivityRange
1754 Increase in volatility Concept (Monetary) For Period Credit cve:TheoreticalImpactToNetEarningsBeforeTaxFromIncreaseInOptionPricingModelSensitivityInputs
1755 Decrease in volatility Concept (Monetary) For Period Credit cve:TheoreticalImpactToNetEarningsBeforeTaxFromDecreaseInOptionPricingModelSensitivityInputs
1756 101610 - Disclosure - Financial Instruments - Summary of Earnings Impact of (Gains) Losses from Risk Management Positions (Detail) Network

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*

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1757 Implied Table Table

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*

 implied:Table
1758 Disclosure Of Financial Instruments [Abstract] Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
1759 Realized (Gain) Loss Concept (Monetary) For Period Credit cve:SettlementsFairValueMeasurementAssetsLiabilities
1760 Unrealized (Gain) Loss Concept (Monetary) For Period Credit cve:GainsLossesRecognisedInProfitOrLossAttributableToChangeInUnrealisedGainsOrLossesOnChangeInFairValueOfDerivatives
1761 (Gain) Loss on Risk Management From Continuing Operations Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnChangeInFairValueOfDerivatives
1762 101620 - Disclosure - Financial Instruments - Summary of Earnings Impact of (Gains) Losses from Risk Management Positions (Parenthetical) (Detail) Network

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*

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1763 Implied Table Table

*

*

 implied:Table
1764 Disclosure Of Financial Instruments [Abstract] Abstract ifrs-full:DisclosureOfFinancialInstrumentsAbstract
1765 Realized (Gain) Loss Concept (Monetary) For Period Credit cve:GainsLossesOnChangeInFairValueOfDerivativesDiscontinuedOperations
1766 101630 - Disclosure - Risk Management - Additional Information (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureRiskManagementAdditionalInformationDetail
1767 Disclosure Of Risk Management Strategy Related To Hedge Accounting [Table] Table

*

*

 ifrs-full:DisclosureOfRiskManagementStrategyRelatedToHedgeAccountingTable
1768 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1769 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1770 Notional Amount of Interest Rate Swaps [member] Member ifrs-full:InterestRateSwapContractMember
1771 Trade receivables [member] Member ifrs-full:TradeReceivablesMember
1772 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1773 Financial assets, class [member] Member ifrs-full:FinancialAssetsMember
1774 Foreign Exchange Contracts [Member] Member cve:ForeignExchangeContractsMember
1775 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1776 Risks [member] Member ifrs-full:TypesOfRisksMember
1777 Credit risk [member] Member ifrs-full:CreditRiskMember
1778 Liquidity risk [member] Member ifrs-full:LiquidityRiskMember
1779 External credit grades [axis] Axis ifrs-full:ExternalCreditGradesAxis
1780 Entity's total for external credit grades [member] Member ifrs-full:EntitysTotalForExternalCreditGradesMember
1781 Investment grade counterparties [member] Member cve:InvestmentGradeCounterpartiesMember
1782 Range [axis] Axis ifrs-full:RangeAxis
1783 Ranges [member] Member ifrs-full:RangesMember
1784 Top of range [Member] Member ifrs-full:TopOfRangeMember
1785 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1786 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1787 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1788 Committed Credit Facility [member] Member cve:CommittedCreditFacilityMember
1789 Classes of contingent liabilities [axis] Axis ifrs-full:ClassesOfContingentLiabilitiesAxis
1790 Contingent liabilities [member] Member ifrs-full:ContingentLiabilitiesMember
1791 Base Shelf Prospectus [Member] Member cve:BaseShelfProspectusMember
1792 Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
1793 Notional Amount Concept (Monetary) As Of ifrs-full:NotionalAmount
1794 Foreign exchange contracts outstanding Concept (Monetary) As Of Debit cve:ForeignExchangeContractsOutstanding
1795 Increase decrease to earnings from change in foreign exchange rate on foreign exchange contracts Concept (Monetary) For Period Credit ifrs-full:GainsLossesOnExchangeDifferencesOnTranslationRecognisedInProfitOrLoss
1796 Amount of Foreign Forward Exchange Contract Concept (Monetary) As Of Credit cve:AmountOfForeignForwardExchangeContract
1797 Unwound amount Concept (Monetary) For Period cve:UnwoundAmount
1798 Risk management gain Concept (Monetary) For Period Credit ifrs-full:GainLossOnDesignationOfFinancialInstrumentAsMeasuredAtFairValueThroughProfitOrLossBecauseCreditDerivativeIsUsedToManageCreditRisk
1799 Percent of accounts receivable held with investment grade counterparties Concept (Percent) As Of cve:PercentageOfCreditExposuresUsingExternalCreditGradingSystem
1800 Number of investment grade counterparties accounted for more than 10% in accounts receivable Concept (Integer) As Of cve:NumberOfDerivativeCounterpartiesWithNetSettlementPositionsGreaterThanTenPercent
1801 Average expected credit loss rate Concept (Percent) As Of ifrs-full:ExpectedCreditLossRate
1802 Target debt to adjusted EBITDA ratio Concept (Percent) For Period cve:TargetDebtToAdjustedEarningsBeforeInterestTaxesDepreciationDepletionAndAmortizationRatio
1803 Cash and cash equivalents Concept (Monetary) As Of Debit ifrs-full:CashAndCashEquivalents
1804 Available on committed credit facility Concept (Monetary) As Of Credit cve:AvailabilityUnderCommittedCreditFacility
1805 Shelf prospectus amount Concept (Monetary) As Of cve:BaseShelfProspectusCapacity
1806 101640 - Disclosure - Risk Management - Net Fair Value of Risk Management Positions (Detail) Network

*

*

 http://www.cenovus.com/20181231/taxonomy/role/DisclosureRiskManagementNetFairValueOfRiskManagementPositionsDetail
1807 Disclosure Of Derivative Financial Instruments [Table] Table

*

*

 cve:DisclosureOfDerivativeFinancialInstrumentsTable
1808 Types Of Financial Instruments Axis cve:TypesOfFinancialInstrumentsAxis
1809 Types Of Financial Instruments Member Member cve:TypesOfFinancialInstrumentsMember
1810 Fair value derivative financial instruments [Member] Member cve:FairValueDerivativeFinancialInstrumentsMember
1811 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1812 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1813 Crude oil contracts [Member] Member cve:CrudeOilContractsMember
1814 Foreign Exchange Contracts [Member] Member cve:ForeignExchangeContractsMember
1815 Classes of financial assets [axis] Axis ifrs-full:ClassesOfFinancialAssetsAxis
1816 Financial assets, class [member] Member ifrs-full:FinancialAssetsMember
1817 Interest rate swap contract [Member] Member ifrs-full:InterestRateSwapContractMember
1818 Financial Instruments Axis cve:FinancialInstrumentsAxis
1819 Financial Instruments Member Member cve:FinancialInstrumentsMember
1820 Brent collars contract term [Member] Member cve:BrentCollarsContractTermMember
1821 West Texas Intermediate Collars for Term One [Member] Member cve:WestTexasIntermediateContractForTermOneMember
1822 Other financial positions [Member] Member cve:OtherFinancialPositionsMember
1823 Range [axis] Axis ifrs-full:RangeAxis
1824 Ranges [member] Member ifrs-full:RangesMember
1825 Top of range [Member] Member ifrs-full:TopOfRangeMember
1826 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1827 Disclosure of Derivative Financial Instruments [Line Items] LineItems cve:DisclosureOfDerivativeFinancialInstrumentsLineItems
1828 Notional Volumes Concept (Decimal) For Period cve:FinancialInstrumentsNotionalVolume
1829 Terms Concept (Text/String) For Period cve:FinancialInstrumentsTerm
1830 Average Price Concept (Decimal) As Of cve:AveragePriceOfFinancialInstrument
1831 Fair Value Asset (Liability) Concept (Monetary) As Of Debit cve:FairValueOfDerivativeFinancialInstrumentsNet
1832 101650 - Disclosure - Risk Management - Impact of Fluctuating Commodity Prices and Interest Rates on Company'S Open Risk Management Positions (Detail) Network

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*

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1833 Disclosure Of Nature And Extent Of Risks Arising From Financial Instruments [Table] Table

*

*

 ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsTable
1834 Types of risks [axis] Axis ifrs-full:TypesOfRisksAxis
1835 Risks [member] Member ifrs-full:TypesOfRisksMember
1836 Commodity Price Risk [Member] Member ifrs-full:CommodityPriceRiskMember
1837 Currency risk [Member] Member ifrs-full:CurrencyRiskMember
1838 Interest Rate Risk [Member] Member ifrs-full:InterestRateRiskMember
1839 Classes of financial instruments [axis] Axis ifrs-full:ClassesOfFinancialInstrumentsAxis
1840 Financial instruments, class [member] Member ifrs-full:ClassesOfFinancialInstrumentsMember
1841 Crude oil contracts [Member] Member cve:CrudeOilContractsMember
1842 Crude oil differential contracts one [Member] Member cve:CrudeOilDifferentialContractsOneMember
1843 Disclosure of Nature and Extent of Risks Arising from Financial Instruments [Line Items] LineItems ifrs-full:DisclosureOfNatureAndExtentOfRisksArisingFromFinancialInstrumentsLineItems
1844 Description of exposure to risk Concept (Text/String) For Period ifrs-full:DescriptionOfExposureToRisk
1845 Sensitivity Range Concept (Text/String) For Period cve:ChangeInPriceEstimationUnderSensitivityAnalysis
1846 Increase Concept (Monetary) As Of Debit cve:TheoreticalImpactToProfitLossFromIncreaseInCrudeOilSensitivity
1847 Decrease Concept (Monetary) As Of Credit cve:TheoreticalImpactToProfitLossFromDecreaseInCrudeOilSensitivity
1848 $0.05 Increase in the Canadian per U.S. Dollar Foreign Exchange Rate Concept (Monetary) For Period Credit cve:TheoreticalImpactToForeignExchangeGainLossFromIncreaseInForeignExchangeRateSensitivity
1849 $0.05 Decrease in the Canadian per U.S. Dollar Foreign Exchange Rate Concept (Monetary) For Period Credit cve:TheoreticalImpactToForeignExchangeGainLossFromDecreaseInForeignExchangeRateSensitivity
1850 50 Basis Points Increase Concept (Monetary) As Of Debit cve:TheoreticalImpactToInterestExpenseFromIncreaseInInterestRateChangeSensitivity
1851 50 Basis Points Decrease Concept (Monetary) As Of Debit cve:TheoreticalImpactToInterestExpenseFromDecreaseInInterestRateChangeSensitivity
1852 101660 - Disclosure - Risk Management - Undiscounted Cash Outflows Relating to Financial Liabilities (Detail) Network

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*

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1853 Disclosure Of Maturity Analysis For Derivative Financial Liabilities [Table] Table

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*

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1854 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1855 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1856 Accounts payable and accrued liabilities [member] Member cve:AccountsPayablesAndAccruedLiabilitiesMember
1857 Risk management liabilities [member] Member cve:RiskManagementLiabilitiesMember
1858 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1859 Contingent Payment [Member] Member cve:ContingentPaymentMember
1860 Other Nonderivative Financial Liabilities [Member] Member cve:OtherNonderivativeFinancialLiabilitiesMember
1861 Maturity [axis] Axis ifrs-full:MaturityAxis
1862 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1863 Less Than 1 Year [Member] Member ifrs-full:NotLaterThanOneYearMember
1864 Years 2 and 3 [Member] Member ifrs-full:LaterThanOneYearAndNotLaterThanThreeYearsMember
1865 Years 4 and 5 [Member] Member ifrs-full:LaterThanThreeYearsAndNotLaterThanFiveYearsMember
1866 5 Years [Member] Member ifrs-full:LaterThanFiveYearsMember
1867 Disclosure of Maturity Analysis for Financial Liabilities [Line Items] LineItems cve:DisclosureOfMaturityAnalysisForFinancialLiabilitiesLineItems
1868 Derivative Financial Instruments Concept (Monetary) As Of Credit ifrs-full:NonderivativeFinancialLiabilitiesUndiscountedCashFlows
1869 101670 - Disclosure - Supplementary Cash Flow Information - Summary of Supplementary Cash Flow Information (Detail) Network

*

*

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1870 Implied Table Table

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1871 Disclosure Of Supplementary Cash Flow Information [Abstract] Abstract cve:DisclosureOfSupplementaryCashFlowInformationAbstract
1872 Interest Paid Concept (Monetary) For Period Credit ifrs-full:InterestPaidClassifiedAsOperatingActivities
1873 Interest Received Concept (Monetary) For Period Debit ifrs-full:InterestReceivedClassifiedAsOperatingActivities
1874 Income Taxes Paid Concept (Monetary) For Period Credit ifrs-full:IncomeTaxesPaidRefund
1875 101680 - Disclosure - Supplementary Cash Flow Information - Summary of Reconciliation of Cash Flows from Financing Activities (Detail) Network

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*

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1876 Disclosure Of Reconciliation Of Liabilities Arising From Financing Activities [Table] Table

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*

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1877 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1878 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1879 Dividends Payable [Member] Member cve:DividendsPayableMember
1880 Current Portion of Long Term Debt [Member] Member cve:CurrentPortionOfLongTermDebtMember
1881 Long Term Debt [Member] Member cve:NonCurrentPortionOfLongTermDebtMember
1882 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1883 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1884 Bridge Credit Facility [Member] Member cve:BridgeCreditFacilityMember
1885 Disclosure Of Reconciliation Of Liabilities Arising From Financing Activities [Line Items] LineItems ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesLineItems
1886 Beginning balance Concept (Monetary) As Of Credit cve:EquityArisingFromFinancingActivities
1887 Beginning balance Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromFinancingActivities
1888 Changes From Financing Cash Flows: Abstract ifrs-full:DisclosureOfReconciliationOfLiabilitiesArisingFromFinancingActivitiesAbstract
1889 Issuance of Long-Term Debt Concept (Monetary) For Period Debit ifrs-full:ProceedsFromNoncurrentBorrowings
1890 Net Issuance (Repayment) of Revolving Long-Term Debt Concept (Monetary) For Period Debit cve:CashFlowsFromUsedInIncreaseDecreaseInNonCurrentRevolvingBorrowings
1891 Issuance of Debt Under Asset Sale Bridge Facility Concept (Monetary) For Period Debit cve:ProceedsFromIssuanceOfDebtUnderCommittedAssetSaleBridgeFacility
1892 (Repayment) of Debt Under Asset Sale Bridge Facility Concept (Monetary) For Period Credit cve:RepaymentOfDebtUnderCommittedAssetSaleBridgeFacility
1893 Dividends Paid Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughFinancingCashFlowsLiabilitiesArisingFromFinancingActivities
1894 (Repayment) of Long-Term Debt Concept (Monetary) For Period Credit ifrs-full:RepaymentsOfNoncurrentBorrowings
1895 Non-Cash Changes: Abstract ifrs-full:ChangesInLiabilitiesArisingFromFinancingActivitiesAbstract
1896 Dividends Declared Concept (Monetary) For Period Credit cve:IncreaseDecreaseThroughDividendsDeclaredLiabilitiesArisingFromFinancingActivities
1897 Foreign Exchange (Gain) Loss Concept (Monetary) For Period Credit ifrs-full:IncreaseDecreaseThroughEffectOfChangesInForeignExchangeRatesLiabilitiesArisingFromFinancingActivities
1898 Finance costs Concept (Monetary) For Period Credit cve:FinanceCostsArisingFromFinancingActivities
1899 Other Concept (Monetary) For Period Credit cve:OtherIncreaseDecreaseArisingFromFinancingActivities
1900 Current Portion of Long-Term Debt Concept (Monetary) As Of Credit ifrs-full:CurrentPortionOfLongtermBorrowings
1901 Ending balance Concept (Monetary) As Of Credit cve:EquityArisingFromFinancingActivities
1902 Ending balance Concept (Monetary) As Of Credit ifrs-full:LiabilitiesArisingFromFinancingActivities
1903 101690 - Disclosure - Commitments and Contingencies - Summary of Future Payments of Commitments (Detail) Network

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1904 Disclosure Of Commitments [Table] Table

*

*

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1905 Maturity [axis] Axis ifrs-full:MaturityAxis
1906 Aggregated time bands [member] Member ifrs-full:AggregatedTimeBandsMember
1907 1 Year [member] Member ifrs-full:NotLaterThanOneYearMember
1908 2 Years [member] Member ifrs-full:LaterThanOneYearAndNotLaterThanTwoYearsMember
1909 Later than two years [Member] Member ifrs-full:LaterThanTwoYearsAndNotLaterThanThreeYearsMember
1910 4 Years [member] Member ifrs-full:LaterThanThreeYearsAndNotLaterThanFourYearsMember
1911 5 Years [Member] Member ifrs-full:LaterThanFourYearsAndNotLaterThanFiveYearsMember
1912 Thereafter [member] Member ifrs-full:LaterThanFiveYearsMember
1913 Disclosure of commitments [Line Items] LineItems cve:DisclosureOfCommitmentsLineItems
1914 Transportation and Storage Concept (Monetary) As Of Credit cve:TransportationAndStorageCommitments
1915 Operating Leases (Building Leases) Concept (Monetary) As Of Credit ifrs-full:MinimumLeasePaymentsPayableUnderNoncancellableOperatingLease
1916 Capital Commitments Concept (Monetary) As Of Credit ifrs-full:ContractualCapitalCommitments
1917 Other Long-Term Commitments Concept (Monetary) As Of Credit cve:OtherLongTermCommitments
1918 Total Payments Concept (Monetary) As Of Credit cve:Commitments
1919 101700 - Disclosure - Commitments and Contingencies - Summary of Future Payments of Commitments (Parenthetical) (Detail) Network

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1920 Disclosure Of Commitments [Table] Table

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*

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1921 Joint operations [axis] Axis ifrs-full:JointOperationsAxis
1922 Entity's total for joint operations [member] Member ifrs-full:EntitysTotalForJointOperationsMember
1923 WRB [Member] Member cve:WRBRefiningLPMember
1924 Disclosure of commitments [Line Items] LineItems cve:DisclosureOfCommitmentsLineItems
1925 Transportation Commitment Concept (Monetary) As Of Credit cve:TransportationCommitmentsSubjectToRegulatoryApprovalOrApprovedButNotYetInService
1926 Percent of ownership in joint operations Concept (Percent) For Period ifrs-full:ProportionOfOwnershipInterestInJointOperation
1927 101710 - Disclosure - Commitments and Contingencies - Additional Information (Detail) Network

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1928 Disclosure Of Commitments And Contingent Liabilities [Table] Table

*

*

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1929 Range [axis] Axis ifrs-full:RangeAxis
1930 Ranges [member] Member ifrs-full:RangesMember
1931 Top of range [Member] Member ifrs-full:TopOfRangeMember
1932 Bottom of range [Member] Member ifrs-full:BottomOfRangeMember
1933 Business combinations [axis] Axis ifrs-full:BusinessCombinationsAxis
1934 Entity's total for business combinations [member] Member ifrs-full:EntitysTotalForBusinessCombinationsMember
1935 ConocoPhillips Company and Certain of its Subsidiaries [Member] Member cve:ConocoPhillipsCompanyAndCertainOfItsSubsidiariesMember
1936 Disclosure of Commitments and Contingent Liabilities [Line Items] LineItems cve:DisclosureOfCommitmentsAndContingentLiabilitiesLineItems
1937 Increase of transportation commitments Concept (Monetary) For Period Credit cve:TransportationCommitmentsIncreaseAmount
1938 Term of agreement Concept (xbrli:durationItemType) For Period cve:TermOfTransportationAgreements
1939 Outstanding letter of credit Concept (Monetary) As Of Credit cve:LettersOfCreditIssuedAsSecurityForPerformance
1940 Decommissioning liabilities Concept (Monetary) As Of Credit ifrs-full:ProvisionForDecommissioningRestorationAndRehabilitationCosts
1941 Quarterly payment tenure Concept (xbrli:durationItemType) For Period cve:ContingentConsiderationPaymentPeriod
1942 Average crude oil price Concept (Decimal) For Period cve:AverageCrudeOilPrice
1943 Estimated fair value of contingent payment Concept (Monetary) As Of Credit ifrs-full:ContingentLiabilitiesRecognisedInBusinessCombination
1944 101720 - Disclosure - Subsequent Event - Additional Information (Detail) Network

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1945 Disclosure Of Nonadjusting Events After Reporting Period [Table] Table

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*

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1946 Non-adjusting events after reporting period [axis] Axis ifrs-full:NonadjustingEventsAfterReportingPeriodAxis
1947 Non-adjusting events after reporting period [member] Member ifrs-full:NonadjustingEventsMember
1948 Events After Reporting Period [Member] Member cve:EventsAfterReportingPeriodMember
1949 Disclosure Of Nonadjusting Events After Reporting Period [Line Items] LineItems ifrs-full:DisclosureOfNonadjustingEventsAfterReportingPeriodLineItems
1950 Payment to repurchase unsecured notes Concept (Monetary) For Period Debit cve:RepurchaseUnsecuredNotes
1951 Cash payment to repurchase unsecured notes Concept (Monetary) For Period Debit cve:CashPaymentToRepurchaseUnsecuredNotes
1952 101730 - Disclosure - Subsequent Event - Summary of Remaining Principal Amount of Unsecured Notes (Detail) Network

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1953 Disclosure Of Detailed Information About Borrowings [Table] Table

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1954 Borrowings by name [axis] Axis ifrs-full:BorrowingsByNameAxis
1955 Borrowings by name [member] Member ifrs-full:BorrowingsByNameMember
1956 5.70 % Due October 15, 2019 [Member] Member cve:FivePointSevenZeroPercentageDueOctoberFifteenTwoThousandNineteenMember
1957 3.00% Due August 15, 2022 [Member] Member cve:ThreePointZeroZeroPercentageDueAugustFifteenTwoThousandTwentyTwoMember
1958 3.80% Due September 15, 2023 [Member] Member cve:ThreePointEightZeroPercentageDueSeptemberFifteenTwoThousandTwentyThreeMember
1959 4.25% Due April 15, 2027 [Member] Member cve:FourPointTwoFivePercentageDueAprilFifteenTwoThousandTwentySevenMember
1960 5.25% Due June 15, 2037 [Member] Member cve:FivePointTwoFivePercentageDueJuneFifteenTwoThousandThirtySevenMember
1961 6.75% Due November 15, 2039 [Member] Member cve:SixPointSevenFivePercentageDueNovemberFifteenTwoThousandThirtyNineMember
1962 4.45% Due September 15, 2042 [Member] Member cve:FourPointFourFivePercentageDueSeptemberFifteenTwoThousandFortyTwoMember
1963 5.20% Due September 15, 2043 [Member] Member cve:FivePointTwoZeroPercentageDueSeptemberFifteenTwoThousandFortyThreeMember
1964 5.40% Due June 15, 2047 [Member] Member cve:FivePointFourZeroPercentageDueJuneFifteenTwoThousandFortySevenMember
1965 Types of financial liabilities [axis] Axis ifrs-full:TypesOfFinancialLiabilitiesAxis
1966 Financial liabilities, type [member] Member ifrs-full:FinancialLiabilitiesTypeMember
1967 Long-term Borrowings [Member] Member ifrs-full:LongtermBorrowingsMember
1968 Non-adjusting events after reporting period [axis] Axis ifrs-full:NonadjustingEventsAfterReportingPeriodAxis
1969 Non-adjusting events after reporting period [member] Member ifrs-full:NonadjustingEventsMember
1970 Nonadjusting Events After Reporting Period [Member] Member cve:NonadjustingEventMember
1971 Disclosure of detailed information about borrowings [line items] LineItems ifrs-full:DisclosureOfDetailedInformationAboutBorrowingsLineItems
1972 Total Debt Principal Concept (Monetary) As Of ifrs-full:NotionalAmount

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